I find it interesting that Apple continues to force their customers in a certain direction even to the point of a negative user experience.
Nobody is forced. Unlike MicroSoft, Apple does not force updates or upgrades. The decision is entirely the user's.
As for the performance hit, I read somewhere (can't remember where, sorry) that if the RDHD has room on it, the performance hit from converting to APFS is relatively small. I seem to recall that it does get worse when the drive is more full and more fragmented. I can't say from experience as I had SSDs when APFS came out. I did have one iMac that had RDHD and that was converted to APFS, but it was a low-use home automation center, so performance wasn't super critical. I didn't notice any adverse impacts. Of course, if you have disk-intensive activity then the impact will be larger.
What Apple does, and has done throughout its life (yes, even back in the "Golden Days" of Steve Jobs) is to move technology relentlessly forward with little to no consideration for folks left in the dust. They changed CPUs, multiple times, and only supported the older tech for a limited time. It's how they work. they also don't retrofit the OS so that you can run older versions of macOS on newer hardware. In general, you cannot run a version older than what was installed at the factory when the machine was made. Again, relentlessly forward, never backward.
The confusion comes in the fact that the hardware is brilliant, lasts a long time and works well, but Apple just keeps moving on, so a 5-6 year old Mac, hardware running perfectly, gets the tag "vintage" or "obsolete" and left in the dust. The reason that doesn't seem to be an issue for Microsoft and Windows is that PCs are, for the most part, not built to last as long, so if one lasts 4-5 years and then dies, that's just the PC-life.
I guess the thing to remember is Apple is at its core a hardware company. They write software to support the hardware, but what they sell is hardware (and now, services). So, in that light, it makes sense that they don't spend a lot of time or effort on old software that they gave away for free years ago. MS is a software company, not hardware, so they have a different perspective and different drivers for decisions. They hold a near-monopoly, but don't want to attract a lot of attention to that, so they keep the masses happy by supporting older software pretty well. The lack of noise from users in turn keeps the government off their backs.
But, again, nobody is "forced" to update/upgrade. The old software still works, as is evident from folks who come here for advice on problems going way back, even to the G series Macs.