Maki disagrees about it twice and she has a lot to say about the power level of someone.
Yuta saying Hakari on the roll might be stronger than him is simply Yuta being kind towards his senpais. Yuta is very kind to people he likes and respects.
Pretty much nothing of notice and he definitely has some wicked Cursed Techniques packed and ready for the proper moment.
He stated that he wants Kenjaku's ass twice. He is definitely saving his strongest attacks vs him or a potential Sukuna encounter.
Maki says "as of now"
Sorcerers grow during battles ( look Yuuji during Shibuy ) and Yuta is on a whole other level.
Kenjaku's demise will be pretty similar to Geto's. Even if the fight starts in a team fight, the final part of the battle will be Yuta vs Kenjaku and Yuta proving Kenjaku wrong about him.
Maki disagreed twice too. She's the author's voice too. Don't rule it out and try to admit that only your panel is fair to point out lol.
Hakari on a roll>Yuta
Yuta>Hakari outside of that.