your mistake is that you are using market cap ratio and calling it dominance. it is like picking up an apple and calling it an orange! just because coinmarketcap.com is dumb enough to use the word "dominance" it doesn't mean it is correct. in fact dominance in a market has nothing to do with market cap specially when it comes to cryptocurrencies where 1 coin can create billions of tokens out of thin air and have billions of dollars worth of market cap and have a bigger "ratio". and none of that billions of tokens even have to enter circulation for it to have that market cap.
I see your point, but you're talking about 'market dominance' in a classic meaning, related to measuring companies' market dominance - such is simply not applicable to cryptos (as there's no revenue involved). "Dominance" is also a word on its own and can be freely used. It's pretty obvious and clear to everyone that CMC's version relates to market cap dominance only. I see no problem here.
I also tend to agree with you, I always thought it was pretty clear that the word dominance was just used to describe the coin with highest total market capitalization, according to the metrics found on coinmarketcap.com.
Market dominance is obviously something completely different, but that's a totally different context to begin with.
but it is all about the context that the term "dominance" is being used in. people aren't just using the term to compare market capitalizations, they are using the term "dominance" to say bitcoin is losing its ground and being replaced by an altcoin. specifically if you look at the usage of it in first cases when it all started you can see it is mostly used when people want to advertise some altcoin that was getting pumped by that time.
besides when you compare market capitalizations you should also consider that fact that market cap of a lot of altcoins is FAKE because their coins are not in circulation. for instance the coins with premine that have not yet released the coins by dumping them on exchanges. if they do it the price of them will fall and consequently their market cap will fall making it more real.
