If the solution is going to be a prompt for every possible reaction, every single time, combat is going to become a nightmarish mishmash of confirmations, more akin to QTEs than actual turn-based combat. Considering that the game isn't based on QTEs, that's counter to what we should be looking for. Going through the whole list of possible reactions at the start of each turn will also lengthen combat, which can already be "slow". What we have isn't ideal, but it's vastly superior to QTE based combat that a steady stream of confirmations could be for reactions. Constantly having to push Yes or No is no different from mashing X. I can play Tomb Raider, or AC 3 if I'm looking for something like that.
Noooo..... reactions are specific things with specific triggers, and are limited in scope by the ruleset; you can use a maximum of one per character per combat round, they're well defined and clear in what can be done and when. You cannot "react with featherfall" at the start of your turn - that's not how reactions work. There is no 'endless stream of confirmations', there is no 'checking every possible reaction at the start of each turn' - You are either commenting disingenuously, or you have misunderstood what reactions are and what a functional reaction system is.
We can, in fact, get there in a crpg - a contemporary game does so, and others on this forum have posted some nice videos of the system in action, actively not slowing down the game... People need to stop saying it can't be done because it already has been. I'd ask what you imagine the "whole list of possible reactions at the start of each turn" is, that you are imagining will be a problem - please; toss a few out there, and name some examples to illustrate your point. If you post up a long list of reactions that would need to be confirmed at the top of each turn/round, and they're factually accurate reactions that would indeed need to be checked at the top of each turn, then you'd probably go along way to convincing people that it would be unwieldy... so... what are your examples? What's the list? Tell me, so that if what you're saying is actually valid I can understand it and revise my own position in that light.