If the study was done collecting data post 2020, and YouTube announced changes in 2019, then what use does the study genuinely have? Potentially the changes You

If the study was done collecting data post 2020, and YouTube announced changes in 2019, then what use does the study genuinely have? Potentially the changes YouTube have made are successful vaguely but again no data prior to compare it to. Would have liked to see deeper dives into specific demographics, concerning both older generations who have more free time, as well as 13-18 year olds. Both groups are hypothetically vulnerable to such content for a variety of reasons and usually without proper supervision.