I respect Null for quite a lot. I think its his site and he can run it how he wants- and he can probably see a lot more bullshit on his end which influences his decisions. However as a mildly train-adjacent American, the reaction notifications were useful for me to know when I was adhering to or deviating from board culture. Id get TMIs if I powerleveled too much and learned that I should either spoiler that or leave it out due to being off topic, clocks if I jumped the gun and posted something someone else already did so I read the thread more thoroughly in the future, etc. I feel the sticker notifications implemented a pretty good self moderating/community moderated system that helps keep the boards functiong, on topic, and not cluttered. Im curious to see how the post quality changes over time now. Maybe it wont, idk.
I bookmarked my reactions recieved page so I dont have to make extra clicks and I will still check on it periodically, but I do miss the bell notifications. I dont know what my overall score was, never cared and didnt even know that was a thing til pretty recent. Overall I dislike the changes. There are workarounds, so nothing has actually been lost, but I do hope there becomes a sticker notification opt in or out in the future.