The real issue is that the community feels disrespected because the CEO is hyper-focused on an IPO and nothing else.
He has slandered an independent developer that is beloved and lied all throughout it.
When people feel part of a community, they want to trust in their leaders, and nobody has any trust anymore.
Another aspect is that the mods/users want to take power back from Reddit's management. This is a way to do it. I think users and mods want Reddit's management to know that they can't just abuse the platform anyway they want.
I also think that's some mob mentality going on right now. Users and mods want to be apart of some kind of protest. It's exciting. It makes people feel like they're doing something good.
Remember those net neutrality protests? Well, no one cares about it anymore.