If a certain action or business practice makes you a scammer, then the time a certain action happened does not matter.
Suppose it is an allowed practice, then. It was plenty tolerated back in 2016 and earlier (AFAICT): loans could be made and liquidated more easily with account sales.
I cannot think of a good analogy but I do not believe that social changes should retroactively punish users. And this is a social (community) change of ideas rather than a rule-based one. I'm not talking about any moderator actions in my previous post, rather the thought process behind tagging account traders in current times.