First, Apple has never been interested in making Macs for gaming. The fact that they ever made any macs that could be used for gaming was purely an accidental byproduct of making macs that could do professional 3d rendering.
Second, Apple prioritizes experience first. The OS is designed from the ground up, not necessarily for ease of use, but to be more pleasant to use than WIndows or Linux. The hardware is designed to make you happy when you look at it, to be quiet and unobtrusive and be easy to set up.
When faced with a choice between making a more powerful computer or making a computer that delivers a more pleasant experience, they choose experience every time. That’s why ram in their laptops maxes out at 16gb - because Intel doesn’t make a laptop chipset that supports more than 16gb of low-power ram, and Apple has decided that a laptop that can sleep for a full month without the battery dying is an important experience feature. They’ve decided that extra thickness and extra weight kill the experience for laptops, so they fetishize making their laptops as thin ahd light as they can manage.
In their desktops, they’ve decided that a thin profile delivers a better experience. If that hampers the upgradability or repairability of their devices, too bad. They’ve decided that a quiet computer is important - even if that means it’s harder to keep the device properly cool. So you have stories of how the trashcan Mac Pro dies easily from overheating. You have computers like the Imac Pro, where the ram access door had to go in order to make it run cool and quiet.
Third, Apple under Tim Cook has their eye riveted a little too tightly to numbers in spreadsheets. If half of Apple’s religion is experience above everything else, the other half is keeping an eye on the bottom line. If it doesn’t make financial sense to pay for a redesigned form factor for the Imac Pro when you can just reuse the regular Imac industrial design, then it doesn’t get a redesign, even though that means, when you accommodate the necessary cooling to keep it from frying it’s 8-core brain, you lose the RAM upgrade door. If it doesn’t make financial sense to do a product refresh for the Mac Pro or the Mac Mini, then they don’t get a product refresh even when they are badly needed from the POV of the tiny number of customers who buy those computers.
The spreadsheet based bottom line religion is what makes Apple release computers with soldered on RAM (reduced part count reduces costs in all kinds of ways) or with only one kind of port (reducing the variety of parts saves almost as much as reducing the number of parts), They do this even when such cost cutting makes a lot of customers like yourself extremely grumpy.