So I don't get that impression because the trading fees are a sideshow.

Coinbase Vault is providing access and liquidity to the whole DeFi market without ever saying it.

Its like not investing in Amazon because you didn't notice AWS. The similarity being limited to there being a non-consumer facing product that might be bigger than the visible one. Coinbase has a lot of growing revenue streams, which has almost nothing to do with the retail platform of non-crypto people looking to buy crypto.