Generally speaking, the set of people who live with the consequences of a decision is not the same set of people who made said decision.

The commenter may not be in a position to make the decision to switch. It's also possible that changing would incur high switching costs - although I'm not sure what they'd be.

We have both, however some teams predate Gitlab option and corporate inertia, politics and a lack of time keep those teams from switching. In a huge company changing anything can be a major pain in the ass.

Corporate inertia?