Not considering the costs of hosting infrastructure for downloads, developing Fediverse integration in software is an extremely complicated task, and retrofitting it into existing software is no joke.
A more realistic starting point is probably to follow them on Mastodon, ( @Retromags ) interacting with their posts and trying to spread them, and to try to build up a fediverse presence for them. Then eventually, if they find that they get the majority of their interactions through the fediverse, they might consider merging their comment sections.
Would it make sense to create a new instance to use an existing forums structure for downloads?
I’m really liking the worth RetroMags is doing, and notice they have 16K members, so I assume it’s about 4K active monthly users....