[serial_dev]

Just another point to consider: sometimes reviewing a PR and getting it up to your standards is significantly more work than doing it yourself.

If you don't have time to implement it, there is a chance you don't have time to review it.

If it is like that, you can simply say you don't have the bandwidth to review, and/or you don't want the feature in your repo. You can emphasize that they can always simply fork the project and do whatever they want with it.