Very interesting. Blockchain analysis is obviously a bit more advanced than that now, but you can still similarly fool it very easily by using things like StonewallX2 or Stowaway transactions via Samourai or Sparrow.
More wallets means more OPSEC required for you to do to keep all of them safe.
I still think that is a far preferable solution to having all your coins stored on a single wallet,
especially if that single wallet is going to be a hot wallet on a phone or computer. If you really can only manage to have a single wallet then you should get a good hardware wallet, but I think most people would be able to have at least a hot wallet for small amounts and a hardware wallet for the bulk of their funds, at a minimum.