Well said, my standards are high in this case.
As my high standard Computer Science professor would say:
Read the )*&^% Manual.
Or in this case, read the documentation for a mod based on its compatibility.
CCIP for 1.0.1.1 was compatible with 1.02b1 even with changes in the Vanilla files. I still released an update. Why? Cause CCIP is built on top of the vanilla game, and there were changes in the vanilla game in between, so I had to merge those changes into CCIP. Just because my mod uses the vanilla files does not mean the devs should not change those files. I do not include vanilla files inside my releases to keep the file size small.
DH is one of the most mod friendly games out there. Seriously, "most posts in mod threads about compatibility", really? Afaik, the mod thread is open to all, and it does not look that way.
For example some mods do not work with the latest beta, but you have to actually re-install the latest stable version since after all it does seem that MODS USE SOME DIRS OF THE VANILLA.
The game engine only does this if a resource is called upon (ex. a string for an event) and is not found within the mod directory but is found inside the vanilla directory. This has
always been how mods have worked. Otherwise, you can't have slim mods with only files that were changed.
As for the not working part, it's incredibly easy to convert an old mod to a new mod. You add one line to policy_effects for each policy slider and you add a few things into misc.txt you can figure out just by placing the old and new misc.txt (use DH Full if you want) side by side. Heck, it works even if you don't update misc.txt for the old map.
Because each beta has features that can be utilized by the mod? Because they want to keep the mod updated? Because it isn't the dev's job to keep mods up to date? Because the devs want to add new features to the base game?
Well said, my standards are high in this case.
Your standards are incredibly unrealistic, infeasible, impracticable, and are completely different than opinions of any modder, developer, or coder. Things don't always "just work". If you want that, go play Steam games (which incidentally break more things than they fix). Heck, as a coder, I
expect software and documentation to be terribly lacking and installers for any linux/open source program to break, to say the least of corporate software (ex. NeverwinterNights2 Patcher always breaking and manual installation of patches, LinuxMint breaking itself via the update manager, Rubyonrails Installer throwing errors, etc.).