Today, when you have a hundred stations from one company reporting, it is easier to drive a record up the charts. I won't go into streaming, views, etc. I think Gavin had the criteria that the station had to produce a certain amount of hours live or generate a local playlist. We were a reporting station, but was too long ago to remember.
Most stations did follow the National charts, but with local sales, callout and research, stations had the freedom to break a small percentage of records on a local/regional level. Yes, you can get similar online stats now, but it was also nice to talk directly to you your local Peaches, Specs stores (South Florida record stores).
In South Florida we broke many Freestyle records (Stevie B., Expose) many imports (Freeez, Nolan Thomas), Electronic Dance (Planet Patrol), and other groups that charted but didnt reach major National pop chart success (SOS Band, Shalamar).
Those records did well is San Diego, Tuscon, New York and Miami, but didn't make noise in Seattle or Topeka (I won't get into demographics). The same could be said for Nirvana records getting zero traction in SFLA.
Today, all singles in the the top 20 that are on corporate station playlists. I guess in the corporate "one playlists fits all" that doesn't matter. I think that stations can use that to their advantage, also with incorporating localism (community outreach).
With the lastest cuts (reduction in force) this week mostly talent and programming, that brings the goal of a single playlist for each format complete. It is no longer about the programming and talent, it is about the ROI and cost reductions. In this pandemic world, it makes sense.