Heel vs Babyface Champ

I’ve been watching late 80s and early 90s WWF, and as someone who came of age in the late 90s/early 00s, it amazes me how rare heel champions were at that time. Was there a specific point when they decided the "babyface chasing" was a nice draw? Also, was this mainly a WWF thing to run faces on top constantly? Thanks!

Yes, the WWF business was of course built on the monster babyface fighting off the heel of the month, with Bruno and then Hogan. The NWA model was the local babyface chasing the heelish World champ. it really wasn’t until HHH in 2002 where they decided to go with a long term heel on top. But it was mostly his philosophy that "the money is in the chase", likely because he grew up idolizing Flair.