It’s interesting how strong the opinions are on the topic of this thread. I tried my first home surround system about ten or fifteen years ago. A 5.1 system that cost about $3,500 all together. Was more than I wanted to spend, and was really disappointed by the sound quality. To the point where I was ready to believe it when I read that digital sound is filled with artifact, and all analog is a better way to go. Years and many dollars later, I found it really was the speakers holding the whole thing back all along. I still have and use that old AVR, and now that I have a good set of speakers, the dialog is clear and the sound is pretty satisfying, even at moderate volume. Used to keep turning the volume higher and higher to try and decipher the muddy dialog, but that never worked, and having a center channel didn’t fix it.
Occasionally, a TV series comes along that’s pretty engaging. One personal favorite was the AMC series Turn, about Washington’s spy ring during the revolutionary war. But most of what we watch is from long ago. Really like Eddie Muller’s Noir Alley. Regardless of how old or new the film is, the soundtrack can significantly benefit from a good sound system.
Got started on multichannel again mostly because of what I read here. So, I used to have the point of view of the OP. For me, it was because the sound quality of the system I had made me think home theater and multichannel wasn’t worth the time, expense and trouble. But then put together a system for multichannel music that’s working out much better, so why not use it for movies too, since the gear is there.