That logic doesn't work.
How many times have we seen companies that boasted about privacy be exposed harvesting and selling data, outright lying or at the very least being very sloppy? Social media, VPNs, hardware wallets, mail providers, etc.
Apple has not been exposed \*so far\*. It may be an indication that they're living up to their promises, but the default position should be that companies don't do what they say and the only way to keep them accountable is for them to be transparent (with open source, end-to-end encryption, and the like).