Been using Cloaked.io for a similar service. The idea is great. Appreciate not having to share as much personal data.

I use the catch all redirects feature of Proton for this. If you have premium and setup your own domains you can just plug any email at that domain into a website and it lands in your inbox. I got three domains setup so one for personal/private, one for registration, one for "don't trust this site but it needs an email."

Elegant solution.