Then maybe you haven't played any tactical or strategic wargames, especially ones that use waypoints for movement orders that can take more than one turn? Unit versus character is like the difference between 'potaytoe' versus 'potahtoe.'
All right, I'll amend my comment to say I don't know of any turn-based games with individual initiative for characters where they carry out orders until told to otherwise. Thinking about it, I do know some phase-based games where each team goes all at once, and you can give orders to units and then execute them all at once.
No, I haven't played any tactical or strategic wargames, but since BG3 is not in that genre, it's not that relevant a comparison.
The reason RTwP feels more immersive to me than TB is because once the next turn begins in a TB game I am totally irrelevant and at the complete mercy of the RNG Gods. I don't even need to pay attention to what happens once the next turn begins. I could walk away and ignore it because I no longer matter to what is happening. No matter what new opportunities present themselves during the turn, and maybe vanish before the end of the turn and thus before my chance to take advantage of an emergent opportunity, my attention is not necessary and totally irrelevant. Whatever is going to happen is going to happen and there isn't a damn thing I can do about it. But during RTwP my total attention is absolutely necessary ever second as I pay close attention to what is happening and how well my last orders are working. My total attention is necessary every second to take advantage of new opportunities that present themselves before the opportunity vanishes. Just because I'm pausing the game I haven't stopped thinking or doing because I am both reacting to what has happened and proactively issuing new orders. So my presence and my attention are absolutely essential all the time unless I need to take a break. Sure the RNG mechanics are still happening in the background, but I can at least make changes on the fly to mitigate or leverage the RNG results in the moment. A pause in the action doesn't mean a break in my involvement. A pause in the action doesn't mean I'm irrelevant. That means I'm MORE relevant.
In a turn-based game, the reason to not walk away is because you need to be thinking of your next move, how you want to react to what the enemy is doing. If you decided to close your eyes and ears and ignore what the enemies are doing in DoS/DoS 2, you wouldn't do as well as someone who actually paid attention. Your presence is not "irrelevant" on an enemy turn.
Yeah, in RTwP you do need to pay close attention, but a lot of that is because you need to cancel what you were doing and reposition a unit to be in a useful place to attack from. That's little more than busy-work.