my client does not use a version higher than 14.x
this is because 14.x is the highest version supported by the current LTS
my client also won't be switching to a later version of unity unless absolutely necessary, specifically if the platforms they're releasing on require it
the reason for this is because if they do, they're stuck with the new ToS that enforces revenue share unless they stick to 2023.1 or maybe 2023.2 when it comes out because THOSE versions are released before the terms change
but anyone who's used unity knows that you shouldn't use the tech streams for production unless absolutely necessary
including them
If you do not want to pay the unity runtime fee, then YOU MUST STICK TO THE UNITY 2022.3.x LTS LINE Do not upgrade to 2023.X!
The language is confusing, but the idea is that the runtime fee does not apply until the version Release in 2024, which is obviously the Unity 2023 LTS (Which will either be called Unity 2023.4, or Unity 2023 LTS... there is some indication that the branding for LTS will change slightly to not have the last number, and the 2023.x product line is scheduled to have 3 tech releases rather than 2.)
Anyways, the argument as I understand it, is Tech releases are not fully supported releases for games, so they don't count as being "released" in the same way as a LTS release does. If you release your game with a 2023.X tech branch, that's the same as releasing it with the LTS in Unity's eyes, so the runtime fee will apply. You gotta stick to 2022 LTS.
SORRY TO BE THE BEARER OF BAD NEWS!