I’m teetering back and forth on whether this would be useful or not.
On one hand I understand it helps limit contain a reply like I would’ve done to yours, which would’ve just been “unfortunately I agree”… Albiet the character limit hindered my full response. The way I see it is it is like a descriptive reaction that doesn’t clutter the topic. For example if I just hearted/liked your reply you have to somewhat assume an interpretation (I realize the solution may just be add more reaction options, though).
One benefit that I could see it it’s another rung in the engagement ladder for people to interact more. My community is very introverted and reluctant to reply, so perhaps this reply-lite may entice them more.