I hate RTWP. The only plus for them is combat is faster in terms of 1 minute in game time is 1 minute in real life; roughly.

What RTWP doesn't have that TB has:

1. I get to manage each character's moves and attacks strategically every round.
2. I don't have to rely on scripts to manage my characters, which means that my characters do exactly what I want them to do and I don't have characters roaming off after some random enemy and triggering more enemies into the fight and thus getting overwhelmed (this happened to me so many times in Neverwinter Nights 2). Scripts also cause unwanted and unexpected things like your characters wasting healing potions, spells, etc. or simply not fighting when they should be.
3. I get to see the characters actually use their spells and abilities and weapons, and I know exactly which they are using and what they are doing. In RTWP, half the time I have no idea what my other party members are doing. I have to constantly pause and switch characters to see what's been cued up in their cue list. Then, sometimes, even that isn't exactly what they are doing two seconds later because they are hit by some spell or ability that messes up what I told them to do.

There are so many other things I hate about it, but these are the biggest. Yes, the combat moves faster, but in order to control RTWP well, you have to pause so freaking much to ensure everyone is actually fighting, actually using what spells and abilities you want them to use, and overall simply NOT dying.

In TB, I see every action that happens and I can plan accordingly to try to coordinate my party's actions. There are no status effects that suddenly pop up out of nowhere that I didn't notice because I'm trying to manage 4-6 characters all at the same time. There are no unexpected scripts being weird and making my characters do weird random things. I control my characters so they act intelligently during each and every round.

And if TB is done well, like in other games like Pathfinder and Solasta, it isn't that slow.

X-Com is a perfect example. In the War of the Chosen DLC for X-Com 2, you can fight HORDES of Zombie-like Lost. Here's an idea! Just like in X-com 2 War of the Chosen, have the creatures that are all the same act on the same round as a unit. So, five goblins move at the same time and all shoot at the same time in Initiative order. It can be just that fast. My MC moves and shoots. It's the goblins' turn. 5 goblins move and attack all at the same time. The game makes 5 rolls to see if they hit all at once. They need an 18 to hit my character and have a +4 to hit. So every goblin that rolls a 14 hits. Damage rolls are also rolled and applied at the same time. Done. Next person's turn in Initiative order. It doesn't have to be one goblin at a time. Goblins fight in packs. So why not have the game group them in units instead of always breaking it out into individual initiative order?

Anyway, that's my two cents on RTWP versus TB. I suck at RTWP. One of the greatest appeals to me about BG3 is that it is TB. I don't care if Larian adds RTWP at some point. Just don't take away my TB.