Tether did defraud people. They lied on their website, claiming a) audits (which they never completed a single one of) and b) 1:1 backing of each Tether with a dollar in the bank (which they didn't have).
You are right, they lied, and people could have been harmed if there were a “bank run” on Tether.
But in practice there was not and nobody suffered any damage, zero, nada, nicht.
While big banks got fined for actually taking money illegally out of people’s pockets and nobody said let’s shut them down
Just because something is built upon fraud doesn't mean it will face imminent collapse. Usually it's events that put notable financial pressure on institutions that reveal their underlying flaws. The extent of the fraud notionally influences how easily it will end up collapsing. Hence why Madoff was able to keep up his scandal for quite a long time.
I don't see where the GP poster wrote anything like "I guess its ok. Might as well pack it up and let them carry on with manipulation, lying and profiting." - could you quote the relevant passage? Did they edit their comment?