They should probably go back to the original invite only flow they used when Gmail launched.
Every account having the ability to invite an only small finite number of new accounts is one way to thwart scammers.
It was not finite, or uniform. I refilled the invites every week or so based on user behavior.
Not really, even "legit" marketing providers have massive automation rigs to warm email addresses, make them behave naturally and email each other in rings for a bit before using them for cold outreach.
So they'd just do this to farm invites if they needed
That's certainly an interesting idea - mostly everybody should know someone who has a gmail account, so if you get a couple invites a month, that should be plenty and the setup would
Well I was about to say destroy scammers, but I just realized that they would send out spam to places where you could gamble your invites for Real Cash(TM) or just straight up buy them.
This would lower the creation of accounts, but then they would be rarer and worth more to spammers, since a spamming gmail would be rare.
And we would hear sob stories of people getting their accounts closed for inviting spammers.
Not without some kind of delay function and probably filtering/evaluation of which new accounts get this capability...
Everyone here should be familiar with exponential growth of n-ary trees. If you can get one of these accounts and each new invitee gets to invite 2 more, you can already have accounts gone wild.