I've been playing The Quarry on PS5 which is basically a game of quick time events and it got me thinking about reactions. I think others have suggested this before, but what if reactions played out more like a QTE? Zoom in on the character as the attack comes hurdling towards them in slow motion. Then all available reaction options show up on screen to choose from with a clock/timer winding down. It would make reactions a little flashier than a simple popup and maybe add a little gamification of trying to decide what to do before the timer runs out. I don't know if that would get annoying if it happened constantly but... just a thought.
I'd be fine with this, if there was a setting to make the timer last an infinite amount of time :P
In seriousness, I don't think there should be any (real) time-dependent things in a TB game. If I leave to go to the bathroom after my character's turn, when I return I should have missed no opportunities to take actions. Either all the enemies/other players should have gotten through their turns (with my character possibly taking automatic reactions), or I should have a prompt waiting for me.
If I had to choose between BG3's current reaction system and a QTE pop up system, I'd choose the current system (unless Larian also implemented a full-game pause).