Another way to look at it: Prices are up 50% since November if you buy everything in Bitcoin.
When Bitcoin's fiat-denominated value drops, the claim that the price of everything actually increased while Bitcoin remains stable — becomes a clearly silly argument when you realize we can make the exact same argument for literally any other asset of your choice (which will in some cases yield completely contradictory conclusions about whether the price of everything else is going up, or down).
To make this argument, you are essentially axiomatically proclaiming that the value of X is fixed, and so when its value appears to drop relative to other things, this therefore is actually just a case of everything else getting more expensive.
The problem is you actually have to justify why you believe the value of X is fixed; otherwise, the conclusion is tautological. Without justification, you will find endless logical contradictions by applying the same logic simultaneously to multiple assets, yielding stark disagreement/contradiction on whether "everything else" went up or down in value, depending on which asset you chose as your denomination reference point :)
My new point is simply this: You can make this argument about anything whose value declines relative to other things; it doesn't make it a useful interpretation of the actual market trends.
For example, I could say that the price of computational resources hasn't been falling over the past few decades due to advances in computer efficiency an speed; no, rather I claim that this is just an illusion -- the cost of computation has actually remained fixed, while the price of literally everything else in the world has been rising, as long as we denominate them in terms of computational resources! But this is silly and doesn't reflect what's actually happening, because I'm subtly making an axiomatic/unfalsifiable assertion here (that the 'true cost' of computational resources is fixed).
It might be easy to misconstrue as reflective of truth because many things do rise in cost, so it intuitively might seem like a profound alternate viewpoint on reality that logically checks out. But, in reality, the viewpoint is simply wrong / not useful -- a reflection merely of an axiomatic assertion yielding a tautological claim, with no external evidence to back it up.