Capital gains tax is just a % of your gains. So assuming the appreciation of your asset is due entirely to inflation, capital gains tax will be strictly less than the depreciation of the same amount of cash.
If it's a wealth tax, it is giving the best deal to the people with the most non-cash assets, i.e. the wealthy.
The asset has a nominal increase in value but not a real increase. After paying the capital gains tax you end up with less than what you had. In real terms your wealth has diminished. I think people are conflating a speculative asset bubble with inflation on the basis that they tend to occur at the same time and for the same reasons - easy monetary policy. But it does not necessarily follow that if you have inflation you also have a speculative asset bubble.
If it's a wealth tax, it is giving the best deal to the people with the most non-cash assets, i.e. the wealthy.