market cap is a very easy to manipulate metric for the shitcoin masters. there are new shitcoins popping up every day, always diluting such charts. their market cap is mostly made up. the market cap for the bigger shitcoins is also heavily manipulated. the creators of those shitcoins have a strong incentive to get into the top ten. they apply all kinds of tricks to achieve that, for example wash trading.

if you just look at the actual value throughput bitcoin dominance is way over 90%

also, there are disputes over what shitcoins to even count. if only "money" coins are counted btc dominance is also over 90%

https://bitcoindominance.com/