This is interesting. I'm glad they got input from the actual people doing the mixing! I haven't personally experienced this problem really, and I guess now I know why. I don't watch a ton of new stuff, and when I do it's off a disc, and with a modern multi-channel speaker setup.
I figured this phenomenon was mostly because people have largely been tricked into assuming they don't need speakers anymore, and that certainly seems to be a significant factor. But the specs from streaming service platforms seem to be a bigger core issue. They're wildly inconsistent both in standardization and in codec playback.
We can't fix the problems with the streaming services, at least not until they die out, which is a lot closer than people seem to be willing to accept. But you can seriously mitigate that problem with some speakers. Not a soundbar. That's snake oil shit to part boomers from their pensions. People spend all this money on gorgeous LG OLEDs and then when they can't hear jack shit in anything they're watching, they just throw their hands up and go "well darn, that's just how it is". I realize no one wants to hear this because they don't want to spend more money and put more Stuff in their homes but it's not an optional thing. If you want to watch or play any modern media, you need modern hardware. You could get away with it in the CRT days because those were big enough that they could fit some decently sized speaker cones in the sets themselves. But as soon as the HD flatpanel era started, that went out the window and never came back. The speakers in your TV or soundbar aren't "fine", you're just used to it, convenient strawman I've just constructed. The human ear is a lot better at growing accustomed to Weird Shit than the eyes are.
The reality is that if you want to hear shit, you need speakers. They're cheaper than ever, but you can get even better ones at a thrift store for a few dollars. You don't need to go full-on Atmos or whatever, though that shit does rule. Just . . . Please, I implore you, love yourself more than this. Go get a cheap receiver and some speakers and stop putting up with a shitty experience.