All sorts of things are still useful with email, for instance my work sends my duty rosters to my personal email address (my preference so I don’t have to log into work when I’m off duty) I get a reminder for my car service, confirmation that my online grocery shopping has been picked and when to expect delivery, confirmation of orders I’ve made and delivery dates times, where I live we have a management company and they communicate to residents by email, some 2FA checks come by email, I still find these things useful & prefer an email rather than endless push notifications on my mobile if that’s an alternative, I don’t allow email to notify my mobile either, I just check the inbox a couple of times a day.