This is pretty interesting. Using the experimental wallet feature at CryptoID it appears that there are over 184,835 addresses it believes are associated to this wallet. I think the deposit pattern is consistent with it being used as a sinking fund to receive exchange transactions and drive up price. The sudden withdrawals are likely to prevent any wallets from getting too big/visible.
I think we may have been observing something similar (albeit at a different wallet) when you noted the reduction in total wallets with balances. Also, the distinction between wallets with and without balances in the image seems to confirm your reasoning in your article above: https://chainz.cryptoid.info/bcc/wallet.dws?28.htm