A product whose early adopters all share a commonality unlike the general public likely has a low ceiling.

For example, imagine a product with a privacy angle where 60% of its early adopters use Duck Duck Go as their primary search engine.

That product is only shown to have market fit with an odd sub-population of the overall market.

Ideally you want your early adopters to look like a random sample of the market you're actually targeting.

Otherwise, you may have only made a product that has market fit in a niche.

If you aspire to be used beyond privacy conscious users, make sure that your early adopters don't disproportionately use Duck Duck Go.