Sensitivity of the PCR test creates unreliability which undermines contact tracing, and destabilises policy making.
Jay Bhattacharya explains that the epidemic is too widespread for contact tracing to limit disease spread; that errors in the PCR tests substantially raise the human costs of contact tracing and render it less effective; and that contact tracing incentivises the public to mislead public health authorities.
https://inference-review.com/article/on-the-futility-of-contact-tracing