[verginer]

Good observation, but they also acknowledge: > there are considerations inherent in our use of the case insensitivity shortcut, which trusts the YouTube search engine to provide all matching results, and which oversamples IDs with letters, rather than numbers or symbols, in their first ten characters. We do not believe these factors meaningfully affect the quality of our data, and as noted above a more direct “brute force” method - even for the purpose of generating a purely random sample

In short I do believe that the sample is valuable, but it is not a true random sample in the spirit that the post is written, there is a heuristic to have "more hits"