I think it's widely thought that there *is* also a new golden age of TV, because there are definitely a lot of high quality series out there. You still have to hunt though. Netflix may have hit it out of the park with House of Cards and Orange Is The New Black when it started. But now we get Emily in Paris... but also The Crown.
I'm certain that the model isn't economical any more. In the old days, there were massive syndication revenues to be achieved (and for some perhaps there still are), but now you have Netflix spending more than they earn, and attempting to make TV shows not just for the US, but the world. The UK is now their number three production base, but Netflix is making TV in pretty much every European country, as well as places like India, Australia and dozens of other places. And they're making movies - they want to win Oscars. And they're making reality TV. And then there's the vast volume of kids stuff that I suspect few of us here are watching.
They need to sign up a hell of lot of people to make their business model work.
Meanwhile Amazon and Apple can essentially subsidise their TV services while they play their game (Amazon can amortise their spend against other Amazon revenues, but I reckon Apple will be out of TV production in a few years' time). But the spending is just a rounding error on their spreadsheets.
If you're HBO Max or Peacock, you have to build an offering that's equal to that of Netflix. Viewers expect it.
It's all got to be unsustainable. And where it leaves traditional networks I have no idea.