There is some justification for such claims. It wouldn’t be effective if there wasn’t a kernel of truth to wrap the lies around.
Communists always use kernels of truth, however, old, irrelevant, or distorted.
As for fentanyl as payback for opium war, it’s irrational. We are not UK and had nothing to do with it. (And of course it was almost two hundred years ago, we were allied with China subsequently and freed them from Japan etc…).
But Chicoms and all Marxists are like ours who invent things like 1619 project. They see all caucasians as the same, colonialists. Nations don’t matter. Our left picked up a lot if not most of their crap from the Chicoms over the past seven decades.