What they have in common is that they have fame and money, and it turns out you can do a lot with that.
Rihanna imo is very savvy and the Fenty brand was a very successful business, involving a couple pivots from fashion to more lingerie and beauty. The big Savage x Fenty musical production event every year is a smart move that leverages her music industry connections and draws lots of interest and new customers.
Arguably she is doing better than Musk atm, given that he started life with a huge capital advantage and is likely losing big on Twitter right now (as well as tanking his public image).
Hence celebrities getting married and divorced every three weeks, it keeps them in the news.
His successes just delivered what the market demanded but established powers did not want to pursue for one reason or another. He knows to outsource actual work to experts and offers them attention which is easier due to his interest in tech/science. Of course, he sees them as tools and he doesn't need to care about labor laws but that's a part of the longer list of his flaws and mistakes.
After Tesla/SpaceX took off, it has been as you described.
Musk example[1] of this, he sold 1 million USD worth of perfume with smell of burnt hair in a few hours.
https://www.reuters.com/lifestyle/oddly-enough/elon-musk-sel...
Elon Musk was barely more than a nobody when he got involved with Tesla and started SpaceX.
Fenty was founded after Rihanna had scored countless hits and was basically a household name.
He was extremely wealthy and had a lot of connections from buying his way into other companies. He was not yet a household name/ global celebrity, only one in more niche (but very powerful) circles, that changed soon after.
If you can reasonably self-fund a startup with employees for a while, you are not a nobody and you are likely far more powerful than 95% of the population. You can literally dictate what other human beings do for 40 hours a week. That's not being a nobody...
> Rihanna is now worth $1.7 billion, Forbes estimates—making her the wealthiest female musician in the world and second only to Oprah Winfrey as the richest female entertainer. But it’s not her music that’s made her so wealthy. The bulk of her fortune (an estimated $1.4 billion) comes from the value of Fenty Beauty, of which Forbes can now confirm she owns 50%. Much of the rest lies in her stake in her lingerie company, Savage x Fenty, worth an estimated $270 million, and her earnings from her career as a chart-topping musician and actress.
https://www.forbes.com/sites/maddieberg/2021/08/04/fentys-fo...
She is a business mogul in the best sense of the word, just in industries far away from here.
I know who Musk is, I know what he does, I know about the companies he founded, I know what he looks like. All I know of Rihanna is that she is a pop star.
Celebrity is very contextual.
Probably that estimate would be lower now, given the market downturn. But clearly she’s well on her way to building up a competitor to the established brands.
And while it's true that VSCO's current market cap is 3 billion, at the time that Rihanna made her comment VSCO's market cap was 5-6 billion. It has dropped significantly in recent months.
Also, don't forget that Rihanna has something the top three beauty supply companies don't have - a growing brand. That has a massive impact on market cap.