The reason for altcoin projects leaking in, in Project Development, can be this:
Project DevelopmentOrganization of Bitcoin and related projects, bounty campaigns, advertising etc.
The tag under it clearly says that bounty campaigns or advertising stuff can also be placed in here. That would definitely draw some traffic from Altcoins to this board. Maybe that tagline should be modified so that people don't post projects that are not involving Bitcoin in any way since the board is in Bitcoin sub-forum. And users can report threads for being off-board so that mods can move them to where they belong.
Bitcoin discussion is always going to get spammed with altcoin related topics because its the first board people see. I don't really have a solution for that.
It doesn't require any solution since Altcoin sub-forum has its own discussion board named
Altcoin Discussion. Any topics related to altcoins posted in
Bitcoin Discussion should be reported immediately and would get moved (if useful) or trashed as soon as a mod checks the report.
Technical support is kind of a niche board that could touch upon some of the more technical sides of altcoins.
That's true. Having a separate board for Altcoin technical support would help categorize the technical stuff between Bitcoin and other cryptocurrencies.
I know that theres so many altcoins to discuss but popular ones could maybe have their own boards too.
That doesn't seem to be a necessity to me. Any cryptocurrency other than Bitcoin should only be discussed in Altcoins sub-forum since they are all alternative cryptocurrencies, no matter how popular they are. It is not only one or two altcoins that are popular, but they are many, and providing different boards for each one of them would mean a lot more moderation and even more open space for spammers. The forum already lacks moderation in some existing boards, and adding more to them would only make it worse.