I think you quoted the wrong number for Okta's revenue. The first hit on Google said:
> Okta revenue for the twelve months ending October 31, 2020 was $768M, a 43.77% increase year-over-year.
Okta annual revenue for 2020 was $586M, a 46.79% increase from 2019.
Okta, 2020 Revenue: $586M
Sailpoint, 2020 Revenue: $355M
Ping: 2020 Revenue: $224M
Auth0, 2020 Revenue: $200M
There's also Oracle ID Manager, some IBM thing etc - a bunch of other large vendors.