Because most of it was "COVID theater" rather than intended to actually make people safer, the public cannot see the [likely more effective] things you're suggesting.
Same thing with checking temperature at the door (it doesn't work because people can either never get a fever or be infectious before/after one).
Even when it comes to masks we still have very few of the public using well fitting N95 and manufacturers mass-producing masks that barely even cover the side of people's faces (i.e. they don't work as well as they could, even for cloth!).
This was totally forgivable in the early days since "better than nothing" masks, but it has been almost a year and effective mask/mask usage still isn't being promoted nor guidelines for producing high quality masks exists.
Same thing with checking temperature at the door (it doesn't work because people can either never get a fever or be infectious before/after one).
Even when it comes to masks we still have very few of the public using well fitting N95 and manufacturers mass-producing masks that barely even cover the side of people's faces (i.e. they don't work as well as they could, even for cloth!).
This was totally forgivable in the early days since "better than nothing" masks, but it has been almost a year and effective mask/mask usage still isn't being promoted nor guidelines for producing high quality masks exists.