There are some Fediverse services which are incompatible or don’t work that perfectly with each other (e.g. Lemmy on Mastodon). So I was curious on why that could be a problem with ActivityPub compatible software in general. I mean, apparently just implementing ActivityPub may not be enough.
And if there are some Lemmy devs reading, what are some technical difficulties for Lemmy on that regard? Thank you for making this awesome piece of software btw!
In addition to what @Austin_Skeldon@lemmy.ml says, another problem is that each software prefers to implement things in their own way, and not in the way that would be most compatible with other software. This is partly the fault of Activitypub, because its such a generic protocol that the same information can usually be represented in many different ways.
Another big problem is funding and thus developer time. Only few devs are paid to work on Fediverse software, and its not enough to keep up with all the work. So compromises have to be made, and often a nice user interface or other features are seen as more important than perfect federation.