That is true, and I'm making some assumptions myself as well. I'm assuming the combat speed will be improved by release. I Highly doubt it will be released the way it is now because the biggest issue is how long the AI is taking to make their moves / decisions which I fully believe will be improved on. I'm not denying there is an issue with combat the way it is. But I also feel that a game being Turn Based is not a death sentence to a DnD game especially a 5e game. We have enough pseudo DnD games, I want a real DnD 5e game, and really do hope they iron out some of the issues with the current combat.
but if I had to choose RTwP or Turn Based for a 5e game. 100% of the time I will take Turn Based. For multitudes of reasons and not restrict my thinking to hey BG1/BG2 where RTwP so BG3 needs to be as well. I'm looking at the systems they are based on and the potential of the game being built in that system. Honestly who doesn't want an awesome game that is as close to a true DnD experience as possible.
The game having TB combat is not at all a "death sentence." I don't think anyone has said that. The game has already sold pretty well and will no doubt be financially successful, simply because it is a D&D game and it is called 'Baldur's Gate.'
I am someone who does not want a game that is as close to a true D&D experience as possible, because I want a video game and do not want a tabletop experience. So I want things to be changed from standard D&D mechanics wherever that would improve the game relative to providing a good VIDEO game experience.