> 2: when you must use google, make separate, carefully unconnected accounts for each project.

How can one make this advice actionable? Creating new Google accounts requires providing a phone number to which one has long-term access (as they will sometimes require you to do SMS 2FA, even with 2FA off, when logging in). Using one on a different Google account links them (and could cause multiple accounts to get nuked), and you can't use a Google Voice number.

For some things I've taken to buying "aged" Google accounts on forums when I need true non-linkability, but in general this is an unsolved problem. I'd lose several accounts simultaneously if I hit the big G's antispam, as I've had to reuse some phone numbers several times.