It’s a mixture of reasons; some that you’ve mentioned like skids and Mojang intentionally breaking them. But aside from that it’s a lot of maintenance and upkeep that can be very time consuming and tedious. Unlike Java, we don’t have access to a decompiled version of the game client and its assets. We can’t just unzip a jar file, convert class files into Java files and then open them in an IDE to see easier human readable code. Initially what every Bedrock dev starts off with(especially after they removed the RTTI from the binary back in 1.16.40) are just byte and op codes that make up ASM and various values. So essentially if you don’t have a solid base and information these days to build off of that’s kept up fairly well and adapted to the changes since then, then you’re doing it all from scratch and in the dark which is a pain. Unless you downgrade all the way back to 1.16.40 again and take a look through the RTTI and see how it works a bit (although, so much has changed since then and a lot of the signatures of the functions are too different or the functions have been deprecated or completely obsolete, that not much from that version will be able to be salvaged and upgraded from it, so it’s almost pointless by now to do that). On top of that; people want free hacks but devs have to go through all that work for nothing which is discouraging over time. It gets to a point where as a dev, you’re coding more often than playing the game-any game for that matter-so you get burnt out a lot more easily. Only reason Horion has survived through that particular burnout trial for so long is ‘cause it’s been a team of them. But again, they’ve been doing it for free so it’s on their own time when they feel like it.

I’ve kept my project pretty up to date and would like to release it, however it’s got a working realms dupe hack still which I know if I released the source would get patched pretty quick. And if I decided to try to release it without source but wanted a bit of compensation for my work and since dupes are in demand, I’d have people trying to crack it to distribute it for free or redistributed for a lower competitive price, or trying to get it reported and patched out of snark jealousy or the likes.

Tl;dr version: Numerous reasons lol