Basics such as chinos and t-shirts do not show that "my assertion is pretty weak" at all, because they aren't "fast fashion". They are staples that remain in style for a long, long time. I'd argue that they serve to support my argument rather than contradict it. I didn't say all clothing is "fast fashion".

As for the second part. My quote was actually 'New "trends" dictated by celebrities and designers every year do nothing but sow personal insecurities and environmental destruction.'

Obviously the phrase "do nothing but" is an absolutism that I should not have used, since it makes it easy for someone to provide a single counter-example to disprove it. I don't deny that self-expression and "art" are positive things. The question is whether those positive effects are worthwhile considering the negative ones. My opinion is that it's not even close. Not by a long shot.

>late stage capitalism or lack environmental taxation allow companies to produce lots of goods without any regard for the environment.

Agreed. But, I think the fashion industry itself is largely morally bankrupt. It preys on peoples insecurities, and environmental externalities more so than (almost) any other.