This is misleading and borderline deceptive. The UK had the option to implement strong restrictions early, in a planned manner. Italy was
forced to implement such measures at a point when the epidemic had already become unmanageable - the disaster was already a fact just waiting to materialize, and the immediate implementation of severe suppression measures was non-optional by that point. The UK had two decent (complementary) choices available early on - immediately and drastically ramp up testing capacity and implement broad, effective testing with containment of cases in order to quickly get control of the epidemic, or implement broader measures to suppress community transmission early on in lieu of testing (or while testing capacity was being increased); it chose a third, extremely risky option, one widely criticized by experts whose criticism turned out to be justified - deliberate facilitation of community transmission. While the rationale behind this strategy may be intuitively appealing at first, it had not been thoroughly evaluated at the time it was proposed and the govt. went all in on it; that took just over another week, by which time the epidemic had - because of the govt's error - become much less manageable. As a consequence,
the UK's epidemic is currently on a much more dangerous trajectory than Italy's was at the same stage of their epidemic. The yields for these strategies are neither linear nor symmetrical; the returns on drastic, costly measures such as strict suppression are exponentially greater if those measures are implemented very early - when you have low rates of community transmission - rather than being implemented a couple of weeks later, when you have an out-of-control epidemic with high rates of community transmission, and the consequences - in terms of social disruption as well as human and financial cost - of implementing such measures a couple of weeks "too early" are far less devastating than the consequences of implementing them a couple of weeks too late.
Sure, and they should've done that a couple of weeks ago. Just to be clear, their reason for not doing the things they're doing now a couple of weeks ago was that they'd settled on a risky strategy that had not been properly vetted at the time, and that was roundly criticized as soon as it was announced to the public.