Here is an interesting read from New York Times on why the supply chain is as discombobulated as it is and how it could be this way for some time. https://www.nytimes.com/2021/10/22/business/shortages-supply-chain.html

On July 23, 2020, the U.S. Trade Representative (USTR) published Federal Register (FR) Notice 85 FR 44563 on certain exclusions from the Section 301 duty related to goods from China ($300B Action – Tranche 4). This would be the HTS 9903.88.15, which is indicated on the line above your normal tariff code. These product exclusions

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