Earlier quoted context omitted.
Slack should add an option to disable reactions for people like this. However, since the sender is expecting their reaction to be seen, Slack should then replace the reaction with a text message matching the reaction: "Ok emoji", "Thumbs up emoji", "Smile face emoji", etc. so that the reaction doesn't just disappear and the intended recipient sees it.
This is the worst possible outcome - now if I’m in a channel with someone who doesn’t like reactions for unarticulated reasons, I am subjected to these notifications and unnecessary clutter? Bollocks.
The person who hates reactions, OTOH, is going to see all these annoying notifications and unnecessary clutter, because he apparently prefers unnecessary clutter rather than a simple emoji. After all, these people are telling us they want others to type out long, wordy messages just to, for instance, acknowledge a prior message. My proposal here would do just this, but require the sender to do nothing different than before.