We’re not directly scaling him to Partial Transformation Gaara, we’re directly scaling him to base Gaara’s sand armor and
downscaling him from Partial Transformation Gaara.
And he only forced Gaara to transform into Shukaku while using
2,000 clones, which obviously isn’t representative of a single Naruto’s output, and when he attacked Gaara, it was when
Gaara hadn’t recovered (C.134) from
being hit by a letter bomb in his weakest spot (C.133). Plus Gaara had been bullying and toying with him beforehand, so it’s pretty clear that he’s superior to Naruto.