Just use different emails for different purposes.
This is the right answer. One email for important personal reasons (banking, tax, bills, etc). One email for social/spammy personal reasons (friends, social media if you are that way inclined, Netflix, etc). One email for work. One email for crypto exchanges. One email (or throwaway email) for this forum. Throwaway emails for everything altcoin, ICO, bounty, airdrop, related.
Given that the majority of new altcoins are outright scams, you have no idea what these people are doing with the details you give them. It goes without saying you should never undergo KYC, but even your email address can be valuable. With very minimal searching you can find databases of crypto-related email addresses for sale, which scammers will use to target you. 2FA, while obviously better than just a password, is still not foolproof.