Thinking a bit about what makes luxury brands work.

The overall quality of a thing is due to its intrinsic qualities, but also external factors (e.g. network effect, its broader ecosystem)

The primary use case of a luxury brand is significantly higher intrinsic quality.

The secondary use case of a luxury brand is signaling to others.

If the brand is well known and coveted, the network effect of that signaling quality can become huge and dominate the primary use case of intrinsic quality.

A common pattern:

A brand starts off being very high quality and develops a reputation for it.

The secondary use case of signaling grows significantly and comes to dominate.

The product creator cuts a few corners in the core product to enable more scale.

This process continues piecemeal over time.

The original valuable proposition (the primary use case) withers away and leaves only superficial quality.

As information about this percolates through the ecosystem (which takes time), the signaling quality also erodes, perhaps explosively.

Once the signaling value has eroded it's impossible to bring it back.