With all due respect, you're one individual and basic color terms for a language are not determined by a single individual. If you look at usage via proxies like Google ngrams[1] or Google trends[2], cyan barely registers, which suggests it hasn't really shifted to a basic color term.
But its frequency still rose by over 300x since the start of the chart, which might suggest that for some people it is a basic color term.
"English" isn't one monolith. Every English speaker speaks their own version, some closer to each other than others, and new features are constantly being added or removed.
The further you have to narrow down the set of speakers for whom it's a basic color term, the less of a basic color term it is for English as a whole. We don't have to have this argument about e.g. orange.
"English" isn't one monolith. Every English speaker speaks their own version, some closer to each other than others, and new features are constantly being added or removed.