None of those countries have banned it they have paused giving it to a certain age group.
They could have all kinds of reasons for doing that. So far Europe has generally been taking an ultra cautious approach and so far they have been wrong
AZ was initially claimed not to work for over 60s. Some countries thought there was not enough data and didn't give it to that age group. They were then shown to be wrong when more data emerged
When the U.K. went for the 12 week gap between vaccine doses it was initially seen as risky and again 'not enough evidence' so other countries stuck to 3 or 4 weeks. Later evidence proved that the U.K. was right in its approach. We have therefore got more people vaccinated and that will save lives.
Taking some positive risks has been good for the U.K. so far. Our use of AZ for older people and the 12 week gap meant we've got more at risk people vaccinated and that will be saving lives. We are in a race against time to avoid a 3rd wave in the Autumn. Europe might have one before then if they don't hurry up.
There's such a thing as opportunity cost. The risk of what you didn't do. It's not always right to be ultra cautious because whilst you are busy avoiding a tiny risk of blood clots more people might be dying of COVID
And more people might be dying and suffering because of prolonged lockdown too.
Other countries will balance it differently depending on their current risk from Covid and their population attitude to and tolerance of risk
It doesn't mean they are right or that the U.K. is hiding anything it's just we came to a different conclusion on the risk: benefit balance