The part where you gave the word your own private meaning was the unclear part. There are no two sides to "progressive". It means thinking the past was bad and

The part where you gave the word your own private meaning was the unclear part. There are no two sides to "progressive". It means thinking the past was bad and that we can make a better, fairer society in the future. Those who think society was better in the past and think the 1950s or even the 1850s or even earlier were the Golden Age aren't progressive upper or lower case. They are regressive by definition.