Your list shows that out of currently 986 known instances only 6 are federated to more than 500 platforms. That not a lot, and show peertube is very fragmented.
You should explain what you mean with "Peertube platforms", are they instances or something else ? I'm curious to know how you know they federated to x number of other "platforms". Is is shown on each "platforms" anywhere ?
That's a huge task you are doing ! Kudos
Oh, ok for the explanation. I didn’t know about the name change. You can find on jounpeertube too. It’s only talking about plateform.