It’s a bit more nuanced than that. The article doesn’t talk about it, but this NYT article touches on how these Chinese sites are exploiting the de minimis exemption loophole to circumvent US anti-forced labor law, which companies have to comply with to keep their supply chain free of slave labor (Uyghurs in Xinjiang for example):
Lawmakers are flagging what they say are likely significant violations of U.S. law by Temu, a popular Chinese shopping platform, accusing it of providing an unchecked channel that allows goods made with forced labor to flow into the United States.