How can they allow full crowd attendance in the games and we have witness jam packed stadiums with no one wearing a mask ?
Has UK overcome the pandemic
No UK hasn't overcome the pandemic. They have a problem with the delta variant at the moment which is rising. The Euro 2020 is the first large scale football event again. From the pictures we see that most people are nkt wearing a mask anymore. The government is aware of the safety risks and uses the event as a trial run. If corona cases are going to soar in 2 weeks, we will likely see harder measures again.
The covid-19 cases are usually identified within the 14 days of the exposure. So if the UK government isn't stopping people to follow the covid protocol and then start the lockdown again after 2 weeks when the number of cases arises, then who cares. The damage would already have been done.
However for the government, the Euro 2020 will be ended by that time and hence the event will be completed successfully with full crowds. Job accomplished.