I think the other GYP maintainers and I would generally be okay with some sort of transition, but up until recently there's been very little activity in GYP itself from the Node folks. Normally the way I'd want to transition the ownership of an open-source project would be to get people up to speed by making them contributors to the project, and then generally work out some sort of transfer once the current maintainers are comfortable with the new people.
It's entirely possible that various Node devs are very familiar with GYP, but have been reluctant to upstream changes or even ask for changes, because perhaps it was perceived that we were only focused on Chromium. And, it's certainly true that GYP has been in "maintenance mode" and not even really maintained for quite some time.
Does it make sense to try and proceed by having yourself and the other Node folks start by being much more active in terms of submitting bug fixes (like you've been doing of late) and proposing changes, and for myself and the other existing committers to try and be much more responsive about reviewing changes? And then we can go from there ...