I am not sure that is completely accurate.
There was a player with lvl 15 or 16 rebounding & nothing else on the TM last week, his salary only went up to $16k or something close.
Most inside players I see listed have the same mid level skill on 2+ talents, I am yet to see any guards listed that have sensational multiskills, most have that level jump shot and strong at best in the other skills, often quite less.
I think (from what I have seen) that eventually the guards will be paid either more or the same as inside players, depending on how many high level skills they have.
Right now the guards being shown to the market have 1 very high skill with the rest lacking, whereas the inside players have 3 similar mid-high levels skills.