That's a sad realization. And HBO lucked out, really, that GRRM is such a lazy sack of shit. If there were already a book resolution, I likely wouldn't give a shit about the show.
Westworld I'm iffy on caring about season 3, Silicon Valley I wrote off a couple years ago because they decided to suck shit. Veep is still funny, but I think this will be the last season.
And that's pretty much it. So yeah, HBO basically has nothing left anymore. They ruined True Detective and Westworld by pumping out a shitty rushed product, which could've been their next line of programming to last them 5-6 seasons.
Edit: They DO still have Curb, but Larry David taking decades off between seasons isn't helping them any.