I agree that the investment dollars are definitely in the higher-end products. But as far as long term strategy - I think camera companies are pretty much screwed. As far as economics are concerned, I think it is not even long term, but medium term where camera companies need to realize that to survive, they will have to drastically cut back on R&D spending. DSLRs had already reached a point where there was little that could be done to improve the cameras from one generation to the next, but luckily for the camera companies, mirrorless gave them an opportunity to make advances in FPS, AF with eye, vehicle and other tracking abilities, and a few other things. But how much farther can they go without further advances being more about hype than actual improvements? If birders are already getting 80-90% of shots in focus, and sports shooters are getting 30 FPS with buffers that don't fill up, it seems like todays generation of cameras will quickly (within perhaps one more generation) reach a point where the vast majority of photographers will be happy with what they have and won't upgrade until they need to. That, of course, is what the camera business was all about before digital. You bought a camera as a tool and used it until it needed to be replaced. Much like the computer business is today where we are now long past is the time where you felt the need to upgrade a home computer because newer models were faster and more efficient and there were real improvements. The computer I have today (not being a computer geek) is essentially the same as the computer I had 2 computer ago (10 to 15 or more years ago?) aside from having a larger hard drive. I get a new computer now when the old one starts having real issues and needs repair.
As sales continue to plummet, camera companies (I believe) will be forced into the same business model or will go under. Each new generation of camera will be only very marginally improved (if at all) and will be aimed at new customers - not up-graders. Far less R&D money will need to be spent. It might be 5 to 10 years between generations. That would work...except...The YouTubers, the forum dwellers, the online reviewers and influencers would kill any company that tries it. The marketing fallout would be disastrous. (Or maybe not...Canon's M50 II was roasted online for being a very minimal upgrade, but consumers don't seem to mind, but I think the enthusiast market would be outraged.) Look how companies get ridiculed today if they use a 4 year old sensor, even when that sensor performs just as well as a newer sensor.
Camera companies will be in a real bind - a bind they may already be feeling when it comes to improving their products with each generation or facing the online wrath. Since sensors have not really improved in a number of years, we now see companies adding a little noise reduction to their RAW files so they "appear" to be improving. Companies hype a certain number of FPS, but in the fine print you find out there are numerous caveats, such as battery life, only certain lenses, etc. Canon, who I believe historically has been reluctant to play that game, now seems to have realized that they have to join the "hype" party to compete with Sony - the leaders of Spec hype for many years now. Sony has understood that bigger numbers mean bigger publicity and better reviews, regardless of actual performance. One recent example is EVF resolution. I've seen a few reviewers faulting the Nikon Z9 for having a lower resolution than Sony (the A1, I would imagine without looking it up). And yet, I've now seen multiple photographers who have experienced both cameras say that the EVF of the NIkon Z9 is better. Most likely, because Nikon is using better glass in their EVF. In my brief experience with Sony, their EVFs were definitely inferior. But as long as the "number" of dots is higher, they seem to win the spec (and hype) battle - and that's where it counts in today's sound bite, YouTube review world. So, the question will be, how can a company survive the spec wars, when the amount of R&D money necessary to continue to try improve products that are already mature will drive them out of business. Don't have an answer to that.