Never have this issue. I'm not being hyperbolic either. I review Kotlin PRs every day and am never lost for context on a type.
I do code review on GitLab all the time, what’s the issue?
No compiler there so the compiler can't tell you the type. No IDE there so the IDE can't tell you the type. You're at the mercy of colleague(s) not to write code like var request = service.call() or, worse, var b = getResult().