I've seen almost no horrific slowness aside from program switching on spinning disks recently. Stuff is pretty fast now, and that mostly useless premature optimization quote is out of fashion so it might even get faster.

I'm not exactly sure what the slowness people talk about is. Even the most bloated of websites are fast.

The one thing that still is an issue is Android load times. It gets a little excited about killing background apps on my phone and will take 10 seconds to open my notetaking app again.

"Everything" is actually not that bad. And what is bad, probably it isn't due to choosing a mainstream compiled language with GC.