For things I know ahead of time I'm going to need to give someone an email for (e.g. the dentist), I'll pre-make that address and have it ready for when they ask for it. For one-offs / unprepared asks for my email I usually just give them my 'main' [email protected] e-mail just for the simplicity... Fastmail does let you use *@personaldomain.com to forward to your main address, but for the rare circumstance in which you need to reply to one of those emails, you do need to configure it in the settings.
Fastmail is probably the best $60/year I spend