I don't think that's the biggest reason to upgrade to a new major (or even minor) version, especially when the previous release(s) are still supported for quite some time.
Catalina, macOS 10.15, for example, didn't stop being supported when Bug Sur, 11.0, was released. In fact, it will still be supported for quite some time. Mojave, 10.14, is supported until late next year and, High Sierra, 10.13, is still supported even today!
Unless there's some new feature that you absolutely just must have, there just really isn't any compelling enough reason for most folks to immediately upgrade to a new .0 release.
In the Windows world, the conventional wisdom -- for probably a decade and a half! -- has been to wait until after SP1 to move to a new major version.
Maybe the younger generation just hasn't been burned (bad) enough (yet) for them to learn not to touch the stove?
Sure can. But that's true only if these machines are part of IT's infrastructure, which is usually the case at large companies.
A lot of places are BYOD and don't have employee Macs on Active Directory.
For $20 bucks, any office or group with a spare Mac can use macOS Server to control this stuff: https://www.apple.com/macos/server/features/
Given some of the horrible security bugs found very shortly after the last few versions of MacOS were released... I strongly disagree.
The saying about known unknowns and unknown unknowns is quite relevant.