I've known several photographers who have lost 25k, 100k+ followings by being banned from instagram for posts that did not break the ToS. This has been devastating to their careers as freelance artists. I wouldn't recommend leaving a more tolerant platform (tumblr) to put all your eggs in a FB owned basket. With instagram, it all seems to depend on who the mod is who got assigned the reported photo to look at. Many of these artists now run a backup instagram and promote it on their primary account about once every 2 weeks to keep a solid follower count on it in case their main gets the hammer.

Same with all sorts of legal cannabis business related pages. I see a lot of seed companies, dispensaries, culture/meme accounts with fallback accounts and bios saying ‘deleted at 25k...’, etcetera. It’s the same situation as consumers have long faced with Facebook, Twitter, Etsy and so forth - they don’t seem to care that other people invest time and money in their accounts, which the company tosses aside so easily.

Class-action lawsuit grounds?

Except for some very fundamental things (AKA "link in bio").

But yes, most artists I know moved away from Tumblr years ago (with great success).

I hope not... Instagram has terrible usability if you don't have a Facebook account and/or don't want to install the app on mobile. Tumblr was at least tolerable in that scenario.

But none of the permissiveness that old Tumblr had. I believe the new TOS for tumblr are still more liberal than the ones for current Instagram.