This thread is where we really go through the debate. There are other threads like this where it’s not as clear but shows it’s been argued about for awhile.
I summarize the arguments in this video:
Here is PFM’s video where he scrapes the population report and finds a small decrease in awarded 10s. However, as I note in my video, in order for the decrease in awarded 10s to signify a grading “harshness” change, we would need to assume that the condition of submitted cards remains the same across years, which is highly unlikely.