Are you actually sending emails from those addresses? Like if you need to drop an email to your bank, do you use the banking one or your personal (or something else)?

No. I've never emailed my bank, and I don't think that's a thing anyway. If I need to contact my bank, I'll either use their secure messaging on their webpage, or call in.

I'd love to have a random email for everything, and I'm kind of moving that way, but I really like having everything get sorted, and doing it based on the receiving address is really nice. I suppose I could do <prefix>-<category>+<uniq id>@<domain>, but I've been lazy so far.

But yeah, it's working so far. If Tuta pisses me off at some point, I'll probably switch everything from my "junk" domain to a handful of Proton email addresses with suffixes. But so far, it's working well enough.