Chris Whitty lacks ambition.
We're at the limits of what we can do because we still have constant, widespread, community transmission - albeit at much lower levels than it was. Pretty much everywhere in England has at least a few new cases every week. Obviously the numbers are much higher in many places.
New outbreaks can pop up anywhere because the virus is still everywhere. If we don't know where the virus is we have to keep everyone away from everyone else.
Many countries now are going for elimination rather than low level containment. Lots of people are sneery about this strategy - 'They're finding new imported cases/they can't keep their borders closed forever.' This is a horrible argument when you think about it - 'You can't stop me from coming into your space and harming you' played out on an international scale.
We can carry on as we are, living in a reservoir of virus. We can decide that everything is fine as long as the reservoir doesn't slosh up past our ankles. The downside is a continuous cycle of lockdown and release, whole cities and regions switched on and off with little notice and little regard for the people who live there, continuous masks, not knowing from one day to the next whether your business can open or whether you can see your mum ... and we'll have to do this indefinitely because this is not a strategy it's a holding pattern.
This is the government gambling everything on there being a vaccine before they run out of money.
Or we could decide to go for elimination and we could learn from other countries that have taken that route. We could aim to reduce new cases to the level where we could identify every single one, work out how it happened and prevent future transmission.
Businesses could reopen confidently and we could all hug our mums confidently if we knew the virus was just not around, and that any outbreaks that did occur would be quickly contained.