The thing is, a "crying wolf" effect has been built up by the government and the media in the last twenty years or more. We were told there would be total ruin from the Millennium Bug. Not long after that, we were going to die from using our mobile phones. Not long after that, Tony Blair spent billions (and countless civilian lives) on his illegal war, having assured us there were weapons of mass destruction.
And when there isn't some catastrophe such as these to scare the public about, the papers (and sometimes the government) tell us there are paedophiles waiting to pounce, immigrants are stealing our jobs, terrorists are lurking around every corner; the end of the world is always nigh. With all this, how do we know that what the government says is true? Remember that "graph of doom" that was projected for mid October, did it happen? They've as good as admitted they exaggerated the Covid death figures, calling it "miscalculating" or "a different way of counting".
If the government and the media weren't constantly catastrophising so many things, and lying all the time (hoping that the public will forget it), people might have more respect for measures such as this for when disaster really happens.
When it all comes out in months or years to come how much the government have lied about this (it will come out, even if the government try to bury it), people will then have much less respect for government restrictions in general. This is starting to happen already, albeit extremely slowly. Some people will be much less likely to take any pandemic seriously after this, because they will remember the lies and spin.
And if the government had the guts to say "we don't know how long this will last" instead of rubbish such as "we can turn this virus around in twelve weeks"; "normalish by Christmas"; "six more months"; (what is it going to be next March? "Just another year, pleeeeeeeeeeeeease be patient"), they might command a little more respect. People are fed up with being lied to.