Sounds like Parler was fusked not scraped from their description.

At an extreme you could fusk shared Google documents. Assuming there's a bug that brings it down from end of the universe timelines, basically you are brute forcing a shared password.

Or is this 'scraping' - ?login=myusername&password=mypassword

It's hard to see someone guessing 1000's of URLs that they have no public link to, to get material end users have deleted being straight forward legal.