Postscript: A potential win-win way forward
My standard byline below could provide a win-win way forward for Justin Sun and the Steem community.

Just as Steemit Inc came with pre-existing obligations to the community regarding the ninja-mined stake that Justin didn't know about, it also came with a ~$400M legal claim against Facebook and Google for banning Steem advertising, which he also didn't know about.

This legal claim is worth far more than the ninja mined stake and is more than enough compensation for what Justin feels he has lost.

Rather than spending his money trying to take over the Steem blockchain, Justin can sign Steemit Inc up for @jpbliberty's crypto class action and participate in the funding of it. It needs less money ($US 2-3M in total) than he has already spent on Steem and has a huge ROI for his Steemit Inc claim alone.

If Justin supports this, it is a huge win for the Steem community also because every Steemian has a claim in this class action based Steem being worth $6.14 when the Ad Ban was announced and being very directly affected by the ad ban. We have great evidence of this from Steem posts.

We are well advanced with a law firm, top barristers, initial funding and US$350M in claimants signed up.

Signup for the Crypto Class Action against Facebook & Google's Crypto Ad Ban