We never saw him do anything particularly impressive either, compared to someone who can tow ocean liners.
And no, by feats Shazam is stronger than Brandon. Brandon lifted a car, Shazam stopped a falling bus and should be as strong as Pedro who held up a falling ferris wheel. Shazam is also quite a bit faster.
Superman wins decisively. Brandon doesn't have the feats to compete. And it isn't a situation like with someone like Homelander, who at least has other superheroes to scale from (though he'd also lose here). Because simply being a Superman-knockoff doesn't necessarily mean you're on the level of actual Superman.
__________________ Never take life seriously. Nobody gets out alive anyway.