I don't seem to understand what TB is? That's just crazy.
Well, you say a lot of weird shit that makes it seem like you don't (passivity, being a spectator, turns that run while you're away). I don't know what games you're thinking of, but that crap doesn't sound like DOS (yes, DOS, Divinity Original Sin, the games made Larian, the makers of the game whose forum you are on).
EXACTLY why/how is that weird. How in the world is it sooooooooooooooooo bloody hard to understand what I've explained? Whether that crap I've been talking about sounds like DOS or not is totally irrelevant since we are supposed to be talking about Baldur's Gate, Baldur's Gate 2, Baldur's Gate 3 and whether or not BG3 will use and should use a RTwP system just like BG & BG2 did, just like the IWD series did. So, either BG3 will play like and FEEL like BG and BG2 or it won't. DOS is irrelevant. It sure seems like you would rather play DOS than Baldur's Gate. I would rather play Baldur's gate. So far it doesn't look like BG3 is going to provide that opportunity. It might look like BG. It might sound like BG. But it won't feel like BG because the play of TB games feels different from the play of RT and RTwP games.
FACT: In an IGoUGo TB game once I end my turn and the computer continues the gameplay and runs the other side's turn I become a spectator. I have issued my orders and once I end my turn I can no longer influence what is going to happen nor what is happening. I can sit there and watch, or I can get up and walk away while the computer takes its turn. Since there is NOTHING I can do about what is happening my presence is totally irrelevant. I could get up and walk away and the end result when the turn runs its course would be EXACTLY the same regardless of whether or not I stick around to watch it. I don't even need to watch what happens to know what happened after I walked away from the computer while it took the other side's turn because I can figure out what happened just by analyzing the results.
Assuming that we are dealing with few enough units, or characters, for me to be able to do my turn in say 2-3 minutes (i.e. 20-30 seconds on average per unit/character with six units/characters) then when I take my next turn it doesn't matter if I spend 2-3 minutes on my turn, or 2-3 hours, or 2-3 days, or 2-3 weeks. It's a turn base game so there is ZERO urgency to it. ZERO immediacy to it. ZERO immergence, because I don't need to solve that puzzle now. I can solve that puzzle at any time. I could spend five minutes deciding what order to give to the first unit/character than pay attention to a movie for a while. Then spend 1 minute on the next unit/character and then watch the movie for a while. Then spend 30 seconds on the third unit/character and then get up and spend about eight minutes making a cup of coffee in my French press before going back to give unit/character three it's order after thinking about for another couple of minutes. Then I could spend 20 minutes thinking about what order to give the fourth unit/character only to decide to change the order I gave to the 2nd character and then give unit/character four it's order after thinking about it a few more minutes. Then give unit/character five its order after one minute, and give unit/character six its order after two minutes, then end the turn and watch the movie some more while the computer plays the other side because once again I am now an irrelevant bystander and observer, or not if I'm not observing the game because I'm watching or doing something else. Whatever is going to happen is going to happen and my attention to it is totally irrelevant.
So, if DOS is a turn based IGoUGo game or a WeGo game (both sides issue their orders at the same time and then both sides run their turn at the same time) then I could play the combat turns in DOS EXACTLY like how I've described here just as if it were any TB IGoUGo tactical wargame. I'd be a passive observer when the computer does the other sides turn IF I bother to observe while the computer runs the other side's turn. Sometimes when I end my turn when playing Panzer Corps 2 or other TB games I get up and go make some coffee or tea or a snack because it doesn't matter it I watch what the other side does during its turn. I can't change or influence anything at that stage of the game because the computer is doing its thing for the other side's turn and the RNG gods are doing their thing and my presence is totally irrelevant to the results. Because my presence only matters when I'm taking my turn, my presence becomes irrelevant again when I end my turn, if we are discussing an IGoUGo TB game. Even if we were talking about an IGoUGo with reaction or a WeGo with reaction the situation remains the same if all reactions are automatic and thus happen without any input from the player. For example, in Panzer Corps 2 my AT units and AA units and Arty units automatically fire supporting fire in reaction to what the the other side does when the necessary conditions are met. All units automatically fire defensively if they are attacked by an adjacent unit. Arty units return fire if another Arty unit fires on them. Big gun Arty units automatically fire counterbattery fire in support of other targets if the right conditions are met. I don't have to do, and cannot do, anything about what happens because it all happens automatically once I end my turn.
On the other hand, some IGoUGo with reaction and WeGo with reaction TB games can involve more interactivity when the reaction opportunities require a decision by the player. Such as in Steel Panthers when the player has to decide whether or not a unit fires when an enemy unit moves within the engagement range that has been set for it. So, for example, if I have a German 88 sitting on a hill with its engagement range set at 15 hexes (750 yards if memory serves) then I get an option to fire at every enemy unit that moves within that range. If I choose to not fire on the first unit that gets within 15 hexes it moves to 14 hexes and I get to fire again if I want. If I don't fire at 14 hexes it moves again until it expends all of its movement points or I fire on it. And as long as my 88 has a LOS on that target or any other target I get a chance to fire every time a unit within range moves another hex closer. If I don't fire on the first unit that gets within range I get the same opportunities on each succeeding target that comes within range. If I held all reaction fire until after all enemy units stopped moving I get one final opportunity to fire any and all of my units at any targets within range, and enemy units can fire back at anything target they spot and is within range if it has LOS. Phased WeGo with both auto and non-auto reaction is the next best thing to RTwP because the player's attention is absolutely necessary for making those reaction decisions. But in a standard IGoUGo TB game the player is an irrelevant observer when the other side takes its turn.