I think it can be pretty safely agreed that in-person research is better than remote research.
It should also be fairly clear however that remote research is usually cheaper than in-person research.
I wonder; has there ever been an attempt to compare the relative costs and benefits of the two?
I know this has been done in areas such as how many participants you should have when usability testing, with the cost to reward famously trailing off after about 5 people.
Of course, in practice there’s a huge amount of considerations to make about whether remote or in person is the right choice for the particular research you are running and there will never be a single correct answer. But any attempts at trying to find some numbers in some given situations would be very interesting to see.