Not being more powerful doesn't mean you can't compare, lol. Lucas himself said Anakin was "as strong" as Sidious. Palpatine himself admits to Dooku in the RotS novel that Anakin is potentially more powerful than himself. Yoda, Mace and various other Jedi recognize Anakin as the probably most powerful Jedi, which is cemented as fact by a variety of objective sources. Whether we're discussing Legends or Canon, that is an indisputable fact.
Where Anakin lags behind in comparison to Sidious is Force knowledge and mastery, though he's quite underrated there. But in anything else, he's in Sheev's league.