What bodes for the future of this correlation?
https://coinmarketcap.com/charts/#dominance-percentage
The amount of altcoins and tokens being launched went parabolic in 2017. That's a big reason why dominance fell and also why I don't expect it to recover. As long as new coins keep getting churned out, Bitcoin's perceived market share if measured by market cap will keep falling.
I don't think that means Bitcoin is losing its #1 spot or that altcoins are overtaking it. Market cap and dominance are just really bad metrics.
I disagree on your pov, when you disclude the top 10 coins all others combined are about 19% of the total mkt cap. The other coins in the top 10 have gained hugely on bitcoin over the last 2 years, just wondering if this will continue.