I agree, but as something that can easily be used as a 'lever', to be pulled and released in line with infection rates, it is probably easier than opening/closing pubs, schools, workplaces, shops etc. And like all of these things, it doesn't really need 100% compliance. It needs enough compliance to reduce infection rates for a while and I think a lot of people will comply. Even those that don't comply fully might be partially compliant, i.e. smaller gatherings, fewer gatherings and so on.
It would not be too difficult to announce that 'for the next three weeks people in xxx town are not permitted to mix with other households'. Everything else continues - schools stay open, businesses keep trading, and the restriction is lifted when infections slow. Then the cycle starts again, a month or two of relative normality then re-introduce restrictions for a few weeks when the numbers mean they're necessary.
If you timed things right, we could have a Christmas free of restrictions, if the numbers are driven down before hand and if it's accepted that increased family transmission will replace school and workplace transmission. You could even think about extending the school Christmas holidays for a few days, and encouraging workplaces to stay closed between Christmas and New Year.