ActivityPub is the underlying protocol both are built on - it’s what allows posts from lemmy to propagate and be interacted with on kbin and mastodon users comment on both via their existing accounts. Think of it as like email protocol but for social media.
That article is dirt, it makes wild accusations purely based on not understanding how the Irish legislative process works, or more likely assuming it’s readership doesn’t. Its not going to do any good here because it reads like something a nutter would put together when you do have at least the gist of the system.
If you actually want to have an impact share things more in line with the iccl statement and if you’re Irish talk to your local politician, that noyb article doing the rounds will do nobody any favours.