I'm pretty disappointed the Poll only has one or the other, and not a voting option for both. In fact, I'm pretty disappointed in general how much support I see for one option or the other, with no mention of simply showing general demand/support for Larian providing both options. Especially since some of the "arguments" for one or the other option turn extremely vicious, condescending, or insulting.
Larian is an excellent studio with a good track record of not rushing games or cutting corners, I think its extremely fair to hope that they consider themselves financially and developmentally capable of providing both options, it strikes me as incredibly stupid that we as their community aren't making it abundantly clear we absolutely want both, and are accepting of the additional development time/cost that may incur (though I have difficulty thinking it would be some sort of insane difference, as RTwP is fundamentally TB, but with less direct control).
While I respect that previous BG entries have been RTwP, it has some serious issues in terms of making certain classes/playstyles pretty much unplayable. The base D&D rules these games are built on have no allowance for "Well your Wizard cast fireball on Target X, but at the same time that he was casting, Target X ran into melee range of your front line, you just fireballed your front line and there's nothing you can do about it!", or the alternative "You cast Fireball at Square X, all the enemies moved while you were casting, you just fireballed an empty field!". This goes for pretty much any AOE in the previous games.
At the same time, I understand that some people find being stuck with TB for every single fight in games that are admittedly MUCH more combat heavy than the tabletops they are based off of, especially combats with large numbers of unthreatening minions that require little to no strategy to annihilate, can begin to feel very grindy/boring.
So, what is the solution for dealing with the potential drawbacks of either system? HAVE BOTH FOR THE LOVE OF BAAL! Every single person who posts a long-winded, patronizing, argumentative post about why it should be one or the other, without at least starting their rant with "If Its not going to be both, which is the best option, I want it to be...." looks like a complete nincompoop to me. Best case scenario, you try and actually enjoy both systems, allowing you an entire additional playthrough of the game that feels unique from your previous runs. Worst case scenario, you hate one so much you never even try it, but other people buy the game wanting the system you don't, game makes more money, maybe gets additional lifespan/support/content/expansions, you get more game out of your game on the backs of people you disagree with (and insult freely). BOTH WAYS YOU WIN.
TL;DR: PLEASE GOD STOP ARGUING FOR ONE OR THE OTHER WITHOUT AT LEAST MENTIONING "BOTH" IS BY FAR THE BEST POSSIBLE OPTION FOR EVERYONE INVOLVED.