Summary:

- The Motorola flagship costs too much and he's worried it will no longer run on the Pixel 7a that he got for $200 or that there will be any cheap options.

But they said already there would be cheap options, and Motorola has a Moto G series that it would likely use.

- Worried about other stuff that existing Motorola Android phones do, like privacy violations.

...that definitely won't be in GrapheneOS, they wouldn't allow it.

- More things Motorola does as a company that are bad.

The current option being Google means, despite that, Motorola is probably better.