Stripe is way more than Series C/D at this point. Their last fundraising was a Series H that valued them at $95B. That's more than Ford or GM, and more than the big-4 U.S. airlines put together.

I think they still have pretty significant room to grow - Mastercard is worth almost $400B, Visa is $475B. I heard their stock grants are now a fixed dollar amount which converts to a number of shares upon vest rather than grant, though [1], which removes a lot of the upside. If you negotiate $300K/year at Google (as a senior+; I heard junior hires have a new stock plan) and the stock price doubles, you get $600K/year in stock for the remainder of your 4 years. If you negotiate $300K/year at Stripe and they go public at 5x the valuation, your existing shares are now worth 5x as much, but you're still getting $300K/year.

[1] https://www.teamblind.com/post/Stripes-New-Offer-policy-on-R...

Ah that's a really good point, and I didn't realize it at all. I think the other half of my comment stands though.