It's a shame.
I have to agree with you, they've lost alot of market share like you said starting back in the 90s.
They were really good innovators.
I remember back in '93-95 going over to my buddy's house and and showing off his new Kenwood receiver. One of the coolest things about it was the fact that if you lost power to the unit, you could restore all the settings back from the remote thanks to its advanced bidirectional features. If memory serves me well, it was also RF based which was capable of changing settings without line of sight, including from another room as well (not like infrared).
I bought a Kenwood Pro logic receiver second hand from my brother in law back in '98 and still works awesome for 2 channel stereo.
IMO, i think it was more a matter of marketing pressure from the other consumer retail brands. I don't consider Kenwood any worse than JVC, Sony and etc...
Time stands still for no one I guess....