Because AVRs with multiple built-in amplifiers and DSP are cheaper than AVPs?
Disclaimer: I have one of neither.
It was very difficult to understand what AVP means

Well, it's a kind of indistinct "processor" for something.
OK.
I love conspiracy theories and even collect them, but in this case, I beg to differ.
For a long time, everything digital is cheap. The most expensive chip (or 2 chips) DAC in small quantities costs about $ 100, which is absolutely nothing considering the almost complete functionality and parameters. All-digital amplifiers (whatever that means, they exist in the form of a single chip) generally cost a couple of dollars. Switching converters (for powering) are also worth nonsense.
It's not about cost at all.
It is precisely active speakers that bring manufacturers very good profits, it seems, much more than the production of such traditional separate components as amplifiers and so on.
I tend to think that not all consumers love active speakers. For some, they are convenient, but for some, their limitations are simply inconvenient. For example, pulling analog inputs to them is illogical, and using an additional analog-to-digital conversion for speakers is all the more illogical.
There is nothing wrong with active active speakers.
For some, they are enough.
PS
I'm sorry, I don't know a lot about multi-channel systems because I don't use them myself and don't know the people who use them, sometimes it seems to me that all these "home theaters" are something dusty from the early 2000s. It's hard to find a good mastering of a stereo recording, what can we say about this synthetic multichannel
