I think what is more offensive to me is the dramatic pricing increases for non-luxury fashion brands (e.g. Khaite, Jil Sander, Nili Lotan, etc). There are a lot of articles and negative news about how the softening of luxury fashion is an indication that the overall economy is not doing well, but it feels a bit specific to retail. The pricing is offensive, even if you have the money.
Even moreso with how secondhand fashion companies have become normalized and it's pretty easy to get nice designer pieces (sometimes current season and/or new) at 50%+ off retail.
I agree that the whole quiet luxury trend is analogous to streetwear in that it does not require any real thought, investment or design to make nice margins. However, as a consumer it's even more difficult to justify spending $1200 on a poorly manufactured cashmere sweater when you can find the same design for $150-300 on Quince—or if you are savvy finding vintage Johnstons of Elgin or another high quality brand. The quality of the lower end of the market has improved greatly while the quality at the high end has decreased... and yet prices have bifurcated further.