Explanation from Stripe¹:

> Nearly all of Stripe’s codebase is implemented in Ruby running on the default Ruby VM (YARV). Not only did we not need Java VM-level interoperability, choosing either alternative Ruby implementation would have made for a difficult migration path. Stripe relies heavily on gems with native extensions, and as you can imagine, a multi-million line Ruby codebase over time starts to depend on Ruby-the-implementation, not just Ruby-the-language.

¹: https://sorbet.org/blog/2021/07/30/open-sourcing-sorbet-comp...