At what point does an alt-coin become considered legitimate?

I see thousands of them pop up. Many rug. Many die. But some survive. Some even grow big. At what point is an alt considered legitimate? I’m still rather new. I know at one point, Bitcoin was the only one and the coins that came after were considered alts. But now, ETH, BNB, MATIC, etc are all considered legitimate in their own right.

Is it one of those things where popularity becomes undeniable? Even some of the popular ones I see like Safemoon (granted, I don’t know what it really is) still are considered “shitcoins.” Is it about the tokenomics? Popularity? How does it work?