Just so everyone knows, I've played Solasta. I love it a lot. Not as much as BG3, but it's a great game. Typically, the popups aren't that bad. However, there are times it can get annoying, such as with Smite and Uncanny Dodge and Counterspell. Not super annoying, but annoying nonetheless.
But, for most other reactions, and such, it really isn't an issue. A prompt like Composer posted would be a HUGE improvement to the Solasta style reactions.