I get what you're saying and I think your terminology makes sense.
But the way to understand this is to reframe your view of "money" from being some special, neutral thing to just being another asset.
At any given moment, you could own $1000, or some gold, or some bitcoin, or whatever else. There is nothing special about the fact that it's $ you're holding rather than DOGE or SPY.
So imagine a 2-asset world, that has SPY and $ in it. You are holding $1000 right now, and the market goes from 1 SPY = $1 to 1 SPY = $1000. That is a loss. Denominated in SPY, you just lost 999 SPY.
But the way to understand this is to reframe your view of "money" from being some special, neutral thing to just being another asset.
At any given moment, you could own $1000, or some gold, or some bitcoin, or whatever else. There is nothing special about the fact that it's $ you're holding rather than DOGE or SPY.
So imagine a 2-asset world, that has SPY and $ in it. You are holding $1000 right now, and the market goes from 1 SPY = $1 to 1 SPY = $1000. That is a loss. Denominated in SPY, you just lost 999 SPY.