Personally, I think RTwP worked really well for BG1+2 but I don't think it'd be that enjoyable for BG3, a lot of 5e's stuff predicates on having a hard turn based round system with limited actions while AD&D2 had turns being a little looser in the economy of actions with when and how you do things like being able to do something simultaneously with another player (while 5e only has held turns and actions) and therefor translated better to having things like Attacks per Round being Attacks over Time and spell casting times.

But uh that is opinion based on how I looked at the systems, I could be very wrong.