Many of us prefer to hold multiple kind of coins. What do you prefer: holding it in a sigle kind of wallet or have it on a different kind of wallet?
Better it to hold one coin of one address, even you have hardware wallet, you have generate one erc20 wallet when getting new token.
no body know when you have multi token on one address attacked by hacker, when you have one, you only loss one.
Yes, storing one token in a single address would be good but it is also will be so complicated for us to manage them. I would prefer to store my tokens in a single wallet with an extra efforts to keep it safe.