A look at crypto

I can't say I am too familiar with the crypto space, but the part I know the most about is the part that it is a Ponzi scheme. In the sense that you need more and more people in on it to keep it going. This isn't to downplay the success of cryptocurrencies, take Ethereum for example, Its initial release was on July 30th, 2015. So in a matter of 7 years, it has grown from essentially nothing to $2667.30 as of March 9th, 2022. This is without a doubt a success story in the Market. It's not just Ethereum, it's other cryptocurrencies as well Bitcoin, Litecoin, Dogecoin, you name it, we have seen a meteoric rise in its market cap. Now, the individual differences between the blockchains aren't so much important so much as the fundamental goal of all of them. To be a decentralized medium of exchange whose price cannot be determined by any centralized government authority such as the U.S. Federal Reserve, the ECB, etc... So it claims to be this revolutionary part of modern finance, which it may well be. After all, the price of these coins although volatile has only been shown to continue skyrocketing which indicated people are believing the story it is telling. However, dispute this success, the trepidation I am having is understanding that if it really is so revolutionary why is the price of every coin always depicted in USD? Why do we always hear the "new high" or the "new low" these currencies are hitting relative to the USD? Why not talk about the actual inflating or deflating of these currencies as we do with fiats? In my view, it is not the new decentralized medium of finance, it's another glorified fiat.