“Meng did nothing wrong, let her go with a quiet whisper not to come back”

That was absolutely not my read on it here. It's describing a realpolitik situation where Canada is on shaky legal grounds since they are not a signatory to a foreign embargo, and thus overreach their strict legal obligations to please an ally. The suggestion of letting Meng go isn't about her being right or wrong; it's about what's the savviest move Canada could have made here that would have neither pissed off China nor the U.S.

Simply refusing to act on behest of the Trump Administration and giving plausible deniability why isn't defying them. It's a neutral political move. The consequence of not doing so is what we've since experienced: deteriorating relations with a major foreign power with no gains in return with the ally we tried to suck up to.