I think we're in the era of use what you have, and don't worry about the GAS or whatever people call it.
If the X10 Fuji died, I doubt I would replace it with anything. The RX Sony's are OK, but it's not really needed. I can use the phone if I have no camera on me. Not really worthwhile buying an expensive compact unless I would use it.
I can just take the A57 if I want smaller size. I didn't really use the mirrorless ones I did try, even the small body ones - soon as you mount a normal lens, the small size is wiped out.
Prices..well let's put it like this. That new L mount that came out, 50mm F1.4 lens almost 1KG in weight, huge and costs £2200! That's a nuts price for any 50mm f1.4, I'd be embarrassed to advertise a lens like that for that. Even an A7III, mix in a 24-105mm and a 70-200mm F4, that's over £3500 just for a two lens set up. Even Tamron and Sigma are price gouging on their newer lenses, not as much - still prices are bad all round. You can get alright deals on older bodies, lenses have gone up to levels I've never seen before. Can't say I'm surprised to see older cameras around, and people just using them. If I got stuck I'd just re-buy a good s/h A99 or whatever else I needed to replace ie one of the crop bodies. Prices are only going to fall even more over time.
I think the SLT was a compromise, least with some sensors. Perhaps the newer ones a bit less. If that had an effect on sales I don't know. Sony have the option to remove it and just PDAF off the sensor, if they wanted to. It's not just Sony they are all at it, the new Canikon mirrorless lenses are pricey, even the Fuji X ones lack much of a budget range bar a few kit lenses.
I remember when I worked for a major supermarket years ago, I was told quite clearly in no uncertain terms - that branches don't always have the same stock. Some lines (ie the budget stuff), are removed to up sell to more premium lines. It's just how they work, xyz no. of people will need an item and they will probably pay more for it. That worked back then, until the German discount chains came in, and gobbled up a lot of market share. What the camera industry needs badly is some maker from China to shake them up - similar to how Godox have destroyed sales of OEM flashes. I'd not buy a branded OEM flash ever again, grossly overpriced and the Godox stuff has the radio built into all the units, triggers are cheap and reliable. Stuff just works, and is priced fairly.
Makers are a bit in denial, keep releasing new mirrorless mounts, new boutique ultra expensive lenses and ramping prices up. No doubt phones have hit them, but I bet the "good enough crowd" is the main reason sales have bombed. What I have is good enough, so why bother with massive wallet dent to get some nice new features? Market saturation is the downfall of the industry. I don't know how to get out of that, but I think just increasing prices isn't working. I'll also say I look at the camera price buster too, and these "cashback" deals usually have price increases just before - in many cases even with the cashback it's more than it was 6-12 months ago. Consumers are not that dumb