We did follow the test and trace until it escaped.
Actually, we didn't, PHE did a partial test and trace process... and not very successfully. They then abandoned it when 'herd immunity' became the policy.
We still don't have the infrastructure in place to do testing at scale - despite repeated offers from private sector labs, university labs, etc.
Initially everyone coming from at risk area were quarantined (on the Wirral and in mk) but it was doomed to failure as it is highly likely as I said on Saturday it was already spreading in the uk in January. This is very likely the case in Italy too.
You seem to be equating quarantining with tracking and tracing. Quarantine is one aspect of tracking and tracing.
The move from suppression to mitigation and back to suppression were based on the scientific advice at the time.
We don’t know that as, unlike in other countries, the scientific advice the government has acted on hasn’t been published. The government also took actions which were contrary to the established public advice from organisations such as the WHO.
The problem at the moment with testing is not the PCR testing itself it is the logistics of collecting the samples. This would not be helped by having more private sector or university labs. Incidentally the biggest testing facility is a private sector lab.
Again, you’re cherry picking one aspect and presenting it as *the issue*. Sampling is just one issue that is hampering the testing and tracking effort. Another is a lack of capacity to test the samples, which has been amplified by a lack of engagement with providers of potential and decisions taken by PHE early on (such as centralising testing equipment).