I've struggled to understand how the ultimate plan can be priced as high as $99/user/month. What kind of company can afford this service price?

It's the only way to have access to epics, a feature quite standard for Ajile project management. As a result, we're sticking to the Community Edition, so it's a loss of business for GitLab.

GitHub enterprise is much higher and doesn't even include CI/CD. In addition other CI tools I've seen quoted in the $300/seat range.

Gitlab is a steal at a $99 price point compared to other tools.