Binance will be increasing the minimum unlock count of deposits into Ethereum (ETH) network from the current 12 blocks to 64 blocks.

I believe it's out of an abundance of caution to ensure funds are not lost. What's also possible is the finalization times take longer for Eth PoS (or can take longer as an upper bound). The old PoW was probilitisc finality which means a certain probability of being final after X number of confirmations. Where as PoS has actual finality, but there is still some period in time before everything gets confirmed.