theres nothing to disprove because you havent proven anything.
polymorph says you get extraordinary attacks, but not the extraordinary special qualities.
feats are stated to be an extraordinary ability.
nowhere in d&d i can find has feats ever been stated to be an extraordinary special quality.
spells like shapechange don't say they give you all of the feats of the monster your turning into.
so extraordinary abilities are further split into
extraordinary attacks
extraordinary special qualities
and everything that is extraordinary but is not an attack or a special quality.
like the gargoyles freeze ability
https://www.d20srd.org/srd/monsters/gargoyle.htm
its an extraordinary ability but neither an attack or a special quality.
you need to show that feats are extraordinary special quality. calling them an extraordinary ability is not enough to call them a special quality.
so either show a rule text saying feats are an extraordinary special quality
or that all extraordinary abilities must be classified as an attack or special quality
or that shapechange gives all of the target creatures feats like power attack, weapon focus, multiattack, etc.
but thats not possible because alter self directly states racial bonus feats are physical qualities and you gain them while at the same time you dont get extraordinary special qualities of your new form. so the two are separate categories.