All HT is really kind of a mess. The vast majority of buyers of TV’s and music still want zero more speakers or 2. The number of speakers required, extra hardware, wiring, etc. makes it a very unappealing add-in for most homeowners.
I mean, yeah, I have a HT receiver and an integrated in my living room, but of my neighbors 100% of the rest of them have just a TV with TV speakers built in and some portable Bluetooth speakers.
We’ve been through this before with Dolby Pro Logic. There was a rush to convert brands from stereo to 100% HT which ended up being the wrong way to go. It also became prohibitively expensive, I suspect due to the HDMI licensing and copy protection issues, though HDMI came after HT. It seems to have paralyzed Theta Digital for a few years.
Don’t get me wrong, I love HT and it’s technology for movies but in terms of 5.1 or more speakers it is an absolutely niche market compared to 2 channel music systems.