Also because they signed a Paramount exclusive contract for new episodes...
Then cut their season length almost in half and started doing "mini movies" on HBO or some shit
So now there's legal stuff going on and they couldn't release now if they wanted to.
I think it's funny they did what they did, and it's fucking over shitty corporations, but it was just incredibly stupid unless the second streaming company pre-emptively agreed to fight any resulting lawsuits on their behalf.
There's no way they weren't getting sued over that shit.