>Throwing them into the oncall production ops channel and context switch everyone so they can see Homer back into a hedge is another.
This is part of the reason I like the "reactji" of slack / discord / etc. They don't cause a new message notification.
Because of that, they're less interruptive, and you can do some interesting, useful things. Like lightweight interaction - we "seed" an up/down arrow pair for voting, people just click one. Or controlling bots more easily - we use one to add Qs to a queue, others to shut them up when they're being noisy, or there's fancier options: https://codeascraft.com/2018/10/10/etsys-experiment-with-imm...
How is that really any different from someone engaging in off-topic banter in an IRC channel? Humans are being human and I don't really see how the problem as you describe it is somehow specific to non-IRC mediums.
> Humor is a generally positive thing and can't help but improve mental state while working.
Humor is subjective. All you have to do is reference "Office Space"'s "looks like somebody has a case of the Monday's!" scene to realize she thought it was funny, the "someone" did not.
I just turn off notifications on Slack and only pay attention to it when I choose to. As a result, someone being silly with reaction emojis or memes in a channel just doesn't really bother me.
Unless you regard it as inane.
Throwing reaction gifs at a happy birthday/congratulation post is one thing.
Throwing them into the oncall production ops channel and context switch everyone so they can see Homer back into a hedge is another.