Turn based combat is a better system and i dont think there is even an argument of the contrary to be made. RTWP is a terrible system that leads to Basic attacks following a turn based models while spells are cast in real time, this leads to an even stronger case of caster supremacy, one of the prime problems with non 4E DnD.
I dont expect it to be either of course, judging by what Sven said, i expect an action combat system.
But to entertain the point a bit more. RTWP simply is a combat system that is very unrewarding and leads itself to lazy encounter design. In an RTWP system, the player never has to commit to any plan of action, instnatly beeing able to cancel any descision and change it for somehting else, it leads to a lot of frantic pausing. It also invalidates the initiative system from DnD and will lead to a devaluation of one of the primary stats.
The only reason people like RTWP is because of some conservative clinging to the Infinity engine games. Temple of Elemental Evil is the most accurate implementation of any DnD system into a video game engine to date and it used turn based combat. of course it also was a broken mess and took years of modding to make it play properly, and thats why the system was never adopted. Think of it that way. Did the Infinity engine games play like the gold Box games? no they didnt. So why should future DnD games be held back by past glorioes, Larian isnt even using the same base ruleset as infinity engine games.
Furthermore, look at the companies that keep making these kinds of games. Beamdog has basically dug up the corpse of baldurs gate and implemented a bunch of thingst hat already existed as free mods, and to add insult to injury made it impossible to buy the original verison of the game anywhere. and then theres PoE by Obsidian, a game series that since has also implemented Turn based combat because quite frankly its a better system. You dont go around stealing ideas from failed competitors. They failed for a reason. Both of these companies wanted to make BG3, and WOTC shut them down because they couldnt move past their own nostalgia goggles.
The fear of creating new types of gameplay comes from a certain kind of game. Tripple A RPGs, Skyrim, Fallout 4 and the like are known to "dumb down" games. And this is correct. But does OS2 look dumbed down compared to any other CRPG? The fear is unfounded.
And to put a Bandaid on all of that. IF, and i don think it will be that way, but IF we get a turn based System, im 90% sure well get an RTWP option. OS2s engine already allows to attack and cast outside of combat. Turns already are associated with a number of seconds in the game engine. If they use the same combat system, theyll sureley implement RTWP as an option to satiate the Nostalgic Boomer Fans.