Define "not much money" and who are you referring to, as customers for this kind of equipment? There are many aspects to it- online sales, the remaining B&M stores, independent AV dealers/installers, larger custom integrators and anaything in between the last two. Some of this equipment is used in bars/restaurants, schools, churches, retail locations and social spots. Some of it is more industrial/commercial, but consumer gear works well in many projects. Some of it is absolute crap, but it still sells and some of it works for a long time.
I'm seeing that people want to simplify- I'm working for a past customer who's using smart TVs, no AVR, some speakers driven by one stereo receiver (I want to add an amplifier for some zones) and a Sonos PlayBar in one room. It all uses the home network, no universal remotes and a couple of apps (HEOS, for the stereo receiver). Other past customers replace equipment as needed, but some of them are going back to simplicity, too- some installed a home theater for the kids and family enjoyment, but most were never into high end. Still, this stuff needs to be installed and set up, which most people don't want to do for themselves.
A lot of people made a lot of money in the markets, their pay increased and they can afford to replace equipment- for them, they didn't spend as much as the Marantz that you had and the AV-10, so equipment failure is more of an annoyance than anything. People who don't make much still buy smart TVs in large numbers and for them, it's a good thing prices have come down. As an example- my 32" TV stopped working, so I went to Beast Buy to see what they had. Originally, I found one that includes Roku, for about $89. Ridiculous, right? I went back and that one was gone, they didn't have anything at that price, so I walked to the open box shelf- found an Insignia Fire TV for about $62 plus tax. If someone wants a TV that does what it can, why do they need to call someone like me, other than for setup? In that case, they can ask one of their kids.
The market is definitely changing and the geeks caused it, but the MBAs caused reliability to become the elephant in the room. I guess they can tell people "Yeah it's crap, but it's cheap".
According to the Statista link, US consumer electronics revenue is still counted as many billions of dollars.
The link shows positive growth forcast 2023-2030, but there's more to it than just one link.
Audio systems market size was valued at USD 33.4 billion in 2023 and is anticipated to grow at a CAGR of over 5.5% between 2024 and 2032, driven by increasing consumer spendings.
www.gminsights.com