You will learn as much about being a good DM for your home game from watching Critical Role as you would learn to be a considerate lover from watching adult film clips off the internet; it's just not in the same ballpark.
While it may be true that
@Snarf Zagyg might not learn as much about being a good DM for his home game from watching Critical Role, I have personally learned a ton from Mercer and from a host of other streaming DMs. I wouldn't even be playing D&D today if I hadn't got addicted to the 4e podcast Critical Hit (Rodrigo Lopez, who really should have made the Survivor thread). And even though I never played 4e and don't find that game to match my style, I was still inspired by and learned a lot of great things about DMing by listening to the show.
If you want to be a good writer, you don't just write, but read as many authors as you can. If you want to be a good film maker, you need to watch a ton of movies. Want to be a good football player, watch as many games as you can. You still have to hone your craft and discover what works and doesn't work for you and your audience, but being exposed to all kinds of different ideas and ways to do things, as well as watching people fail and succeed in different ways, can give you tools you never knew existed, or that may have taken you years to work out on your own.
The point of advice on the internet or watching live-streams or playing in other peoples games isn't to give you the perfect answer for how to be a good DM for your group, but to give you options to think about, explore, reject or try. Aabria might not be everyone's cup of tea, but
@overgeeked can still learn something from her about how to make their own game better and for someone else it might be the perfect style for the group they play with. And a heated argument about a finer point can end up broadening the understanding of those involved.
I believe that live-streaming shows and podcasts have been an immense boon to the hobby, since previously it was difficult to be exposed to different styles of play. And while some players may try to perfectly emulate a DM they see on a stream and fail spectacularly, they can still learn from that experience and modify their own style, should they choose to try.
I do agree that the best way to become a better DM is to think about and empathize with YOUR players. They are your audience, not a thousand or a million people on the internet. What works for you and them is all that matters, and communication is key. Just like two lovers discussing what they like from the adult film clips they've watched on the internet
Of course, no one should read this post and take it as gospel, rather, I hope they think about it, take what works for them and discard the rest.