I'm in the UK where we do have a generally very reliable postal service, but of those three, it's only the bank card that involves a physical letter for me - and even then I have no idea where my bank cards even are because I just use contactless via my phone/watch nowadays.

My electricity payment is direct debit - though I can pay manually via the app if I wish. The app has the amount on it, and they notify of service changes via the app and email. I suppose that if I ignored the electronic notifications they'd eventually send me a letter.

Even if you do get your statements by post, basically nobody here would pay for it by mail. If you really hate computers, you can pay over the phone, or set up a direct debit by phone/letter, or use a "PayPoint" - which includes most corner shops, supermarkets and post offices. It's also quite common for elderly people to just have one of their younger relatives manage it all for them.