This is completely missing the point. As I said in an earlier comment:

"If you had a Bluetooth keyboard or mouse, then Bluetooth would have been enabled before installing the update, otherwise how could you type or click to install the update in the first place? Also, the same thing happens on Mac laptops with built-in keyboard and trackpad. Moreover, it happens on iPhone too, which has no peripherals."

The point is pretty simple: if you had Bluetooth disabled before an OS update, then it should stay disabled after the update. And likewise, if you had Bluetooth enabled before an OS update, then it should stay enabled after the update! In other words, an OS update should not silently change your settings.

It's astonishing to me that people with Bluetooth keyboards somehow believe that I want their keyboard to stop working. That's absurd.

When I first got this computer basically when it first came out there was a point during the initial setup or it was an update soon after I originally set it up where I had bluetooth enabled and then I rebooted and then Bluetooth wasn't enabled anymore. I think Apple got a lot of complaints about that and now they just want to make sure that it defaults to on no matter what just in case.

That sounds like a bug. It would be strange for Apple to "fix" a bug by introducing a different bug. Why not just fix that bug?

Macs have supported Bluetooth for almost 20 years, as have iPhones since their beginning. It's unclear why, after all that time, this change needed to be made in the year 2020.