We are always veering away from the science for various reasons. That's why laws and requirements are generally made by policy makers and politicians and not scientists. We are always balancing science against other competing criteria like cost, convenience, freedom, practicality, etc.
For example, the science tells us that we could have stopped Covid in it's tracks by a simple global 14 day lockdown of the entire planet back in January 2020. Let it die out in the few individuals who had it at that time and it is erased. But that wasn't politically or practically viable so we did half-measures instead. Which obviously didn't work. Scientifically lockdowns would work perfectly, but in terms of practice they don't because they are never implemented perfectly.
Masks are another example. If everyone on the planet or in the country wore the best N95 masks fitted properly then masks would probably do a great deal to curtail Covid spread. But we don't do that. People wear all kind of junk masks fitted improperly and inconsistently. So a mask mandate is less effective than it might be and possibly completely ineffective.
Policy is about using science in the most effective way, not simply blindly following science when is impractical.
