It's not about what he got, but how he got them.
Imagine Zoro was absolute the same after the timeskip, but during the timeskip instead of being trained by Mihawk he got trained by a random ass gag character, like Hyouzou, even if Zoro was still strong and got all that shit during training, nobody would respect his training from a dude like that when Luffy got trained by the right hand man of Roger himself.
So that's what happens with Sanji, Zoro gets to train with the World Strongest Swordsman and Shank's Rival, Luffy gets to train with Dark King Rayleigh, and what Sanji gets? a bunch of Okama trying to sexually harass him while he keeps running away for two years...
And the worst part is that this fucking time with the Okamas is the setup for all the nose bleed sickness shit later on