It's not about their wealth and who is richer between Elon Musk and Michael Saylor. They are both rich and smart but we are not discussing about their intelligent scores here too. Who is smarter is not important and as Bitcoiners, I think we have a same main concern as "Who has more contributions for Bitcoin adoption and Bitcoin community so far and in the future".
The topic literally says "biggest bitcoin holder". No one is talking about intelligent scores or who has more contributions to the adoption of bitcoin and its community. It's simply who holds the highest number of bitcoin.
Satoshi currently holds the highest number of bitcoin and seeing that he hasn't moved or sold any, he sits comfortably at the top of the list of the biggest holders.