One should assume Law became stronger after the Doflamingo fight (the same as base-Luffy then and on WCI) and during his stay in Wano. Similar to Zoro, and even Sanji a little bit, although he has not shown much (which must also be taken into account), probably deliberately on Oda's part.
I can't even wrap my head around simply assuming, like some, they stay the same all this time (even Law and Luffy.)