Disposable email addresses (one-way emails) are used for a one-time sign-up when someone wants to access content that is only given out in exchange for email address, but you don't want to give away your email address.
This approach is understandable and sometimes ok. If you still want to block such addresses, you can find a list of such mail providers here.
If you know of other providers or find one that no longer exists (yes, the list is old and a bit outdated), I would be happy to hear from you.
Disposable email addresses, also called trash email addresses or fake email addresses
Wegwerf-eMail-Adressen, auch TrashMail-Adressen oder Fake-eMail-Adressen