Larian's New community manager made a post on the forum saying they're still working on Reactions, but are keeping it silent for now.
This is similar to what Swen said over a year ago, but at least it's confirmation that they're trying to make their janky engine support 5e mechanics. It is worrying that over a year of working on this and they don't have something ready to present yet.
2y EA anniversary is October 6th, I think. We will see.
Honestly, if they need more time beyond 2023 to guarantee PROPER system, I'd be fine with that.