

That jump at least had a reason, as a bunch of older software checked if they were running on windows 95 or 98 by checking for “windows 9”.
And what it actually feels like is the jump from windows 3.1 to 95. Because it’s literally the same one.
Win 10 and 11 do also use something like this, though it’s more hidden as it’s the update numbers - they were yearmonth (1507, 1709) and are now yearhalfofyear - 20H1, 21H2.
Major version numbers are used when stuff changes, and especially when shit breaks. Can the latest OS X 10 run the same software and on the same hardware as the first OS X 10? If not, increase the major number.