> that's really out of topic since we are discussing public markets
You said the market cap is “undefined.” That is incorrect. Market cap is price per share times shares outstanding. If a company has shares, its market cap is defined by at least one among several metrics.
It’s actually fundamentally germane to your argument, since in private markets one doesn’t have “large market cap changes because what you are observing is just live betting.” What input you use as “price” is the relevant bit, with the CNBC reductive convention of price = last trade being the source of your problem, not market cap per se.
It’s still absolutely on a market, down to being valued and trading. It’s just not on a public market.