The share of household spending on clothing has gone from 10%+ to under 5% in Western countries. When you're spending that much, it's not a surprise that clothing was "BIFL" both in quality and upkeep (repair rather than replace).

The overall revealed consumer preference has been "more and cheaper", not "less and higher quality", which still exists as a niche if you are willing to go down the tailoring route, not off the peg.