Hes probably a liquidity provider because a common user only got 400 UNI. Thats a very mind blowing amount the best part is its totally free, enjoy your free money OP that is a life changing opportunity. Im also satisfied airdrop beneficiary such a very big help in times like this thanks to Uniswap.
That address posted by the OP has zero transactions on Uniswap or anywhere else except receiving the UNI tokens. Wouldn't liquidity provider have to use the same address for the airdrop? Which would have a record of his/her Uniswap transactions?