The reason why your Twitter was suspended is that I think it is likely to be considered as a spam account. Posting spam is inevitable once the Twitter account is involved in excessive bounty or airdrops.
You only need to improve your Twitter profile, The probability of being ban will be greatly reduced.
Bind your email address and phone number, and don't always change the access IP, and avoid tweets with tags like "ICO", "Crypto", I'm sure if you do this your twitter account will not have any trouble.
Thanks for the tips.
this means it's getting hard for bounty hunters to use twitter
Sorry about that! Indeed, it keeps getting harder to use twitter to do bounty hunt. But as coin8coin8 just said, taking good care of your twitter account and posting not just crypto related stuff on it will help you in not having your account suspended again. Use it as you will normally use your main account, follow stars, tweet, retweet them, like various posts. Good luck!