Because we think the powers that be might not ever let it be "over". Remember that after it became apparent that "two weeks" was a lie, the next lie where the goalposts were moved to was "once a vaccine is widely available".
> Remember that after it became apparent that "two weeks" was a lie...
It wasn't a lie.
First off, significant portions of the population refused to take the measures advised.
Second, it's on you if you took "two weeks to slow the spread" (and yes, it was slow, not stop; https://www.cnbc.com/2020/03/16/trumps-coronavirus-guideline...) as "two weeks to slow the spread and then we're done". That's an absurd misunderstanding of the point of it.
^ Just to be clear, I personally don't think there's some conspiracy. I just think a lot of people aren't reasoning about the level of risk in a rational way. They absolutely were in 2020, but now we have widely-available vaccines.