One might think the employees, investors and users might have some issues with "just shut the entire thing down".
To be fair, they actually had the guts to shut down Vine. They know that they can do the same for Twitter and sunset it.
Perhaps it's for the best to save everyone from themselves.
They shut down vine for business reasons not because of any soul searching. Business is business. 99.9% of companies will NEVER shut down over ethical reasons.
Facebook is deliberately more polarizing (engagement!). Twitter is behind on the state of the art, there.
this is not 2007
I don't understand the point you are attempting to make?
he doesn't control twitter anymore and when he was CEO it's not like he could have shut it down given that there was a board of directors and shareholders that would have opposed it. HIs only recourse would have been to resign.