The only reason we are trying to switch from Skype is for the persistent and searchable history. I say "trying to switch" because about half the company prefers Skype messaging and so now we have to have two clients installed.
Whether people use all of Slack's potential or not it's a different discussion, but I'd rather have the ability to do more if I wanted to than having to look for yet another tool to solve a small problem.
I don't think that means that the default client can't be lean and efficient.
As to web hooks and bots, if you really think that necessitates having it be a bloated Electron app, I don't know what to say.
All of these are dormant features.
> 3rd party integrations
Which are processed on the server.
The complaint is that Slack uses an ungodly amount of resources when they're just sitting idle consuming new messages.