The answer is that those version numbers are the Windows analogue to the “23.10” at the end of “Ubuntu 23.10”. But the difference is that this distinction is invisible to Windows users.
The other difference is updating from 23.04 to 23.10 requires running a separate utility, changing repos, and can often break things (PHP upgrading but things still pointing to the old socket version for example). That’s why it feels like a major upgrade, because it is a lot closer to going from W10 to W11, vs just 23H2 to 24H2 which is invisible.