Whenever there are huge buyins or transfers, there's always some people that tracks them out and I think that even it's sort of defeating a bit of its purpose, still you'll never know who's behind of it.
Am still surprised that people are using what is not to disturb themselves, it never move an inch in me seing millions worth of bitcoin flying up and down the blockchain network, people own them and initiate those transactions, also, these are not just happening now.
100 bitcoins, thousands of Bitcoins. An individual doing it? Most likely related to the companies from the Bitcoin spot etf brokers.
We may have some individuals that rich to have performed such actions, likewise it's most likely attributed to the corporate organizations who could afford buying upto that.