I would be fine with the amount of RAM used, if Slack didn't also materially reduce my battery life, by keeping my CPU — and fan — spun up. Charge-discharge cycle counts are a limited thing. They're directly shortening the lifespan of my hardware, doing that.

Is that really your argument? Slack has a material effect on your hardware life - as opposed to all the other usage? Is slack the only thing you're running?

Why not just use another tab in your existing browser then? Or another service entirely?

Either way, it doesn't change anything in creating a widely used application for the least amount of time and effort. The vast majority of their users will not care or even notice if there was a more efficient native app.

It is the only thing reliably using 10-20% of my laptop's CPU, while idle. Having the Slack iOS app even open drops my battery at least 10%/hour. Even Facebook's app or using a mapping app, actively listening to the GPS birds, don't do that.

My employer dictates the choice of communications tool. I don't just get to "pick another service entirely."

EDIT: And their site's 2FA (which I'm required to use, because $work) also reliably gives me "too many login failures" on the first login attempt, so using it in a browser tab is a non-starter, even without also losing desktop notifications.

With the amount of money they've been given, both by VC and by customers (I know what we pay them per month, and although we're not a small company, we're far from their biggest customer), this quality of software and service is absurd.