I noticed that a user can update the "Reactions" he/she made for a post, but he/she can't update the "Reviews" he/she made about a post.

I think this is inconsistent. I suggest making it possible for a user to update Reactions and Reviews about a post.

By the way, I am talking about a user making Reactions/Reviews about someone else's post, and not about changing Reactions/Reviews that other users made on the user's own post.