Migration actually brings in a net benefit of taxes, meaning more money to spend on services such as the health service than if they weren't there and, as it's a net benefit (they put in more than they take out), then that means an improvement in services is possible compared to if they weren't igrating to the UK.
As for whether the NHS is worse than during a pandemic? It probably isn't (I've had lots of personal experience of waiting in and around casualty the past 2-3 years) but attention is now focussed on it, without a 'reason' for government to hide behind. It's a shame that support has only extended to clapping on doorsteps, really.