Personally, I am not surprised by this one bit.
Facebook just plays by its own rules and expects everyone to just take a number and stand in line.
I know many people who have had their business page closed on facebook without warning, I also have a friend who ran a group with over 40,000 members and it was closed down because 3 people targeted it and claimed it was spam.
Even when she tried to show facebook this was false they didn't even respond to her and closed down the group after 6 years.
Decentralised is the only way forward and platforms like Steemit, DTube, Steepshot and the rest will become more and more popular as it gets exposed to the world.
I have helped 3 people join today and get some decent traffic on my blog which also promotes this great place.
Thanks for sharing.