PSA: On Dec. 1, Google will begin deleting inactive accounts along with their contents -- photos, Gmail messages, Calendar appointments, Drive documents, Contacts and YouTube content.

If you have dormant Bitcoin exchange accounts that you might need to access in the future (for transaction history etc) these might become inaccessible without a valid email address.

Ref: https://www.cnet.com/tech/services-and-software/google-will-start-deleting-old-accounts-in-two-days-heres-how-to-save-your-google-account/