Same reason we're still wearing masks, I'd imagine. It's not necessarily about what is the most effective, it's about increasing the odds.
And more than that, it's about what's seen by politicians, their constituents, the media, and society at large as effective. Safety theater, as another commenter put it.
The most effective thing is to eliminate close contact with anyone you don't live with, but is something all of us can't do. So reducing contact and wearing a mask IS the most effective and realistic measure.
I find apalling that you call it "safety theater". What is YOUR big solution?
It's written on the box : does not stop germs or viruses. A mask is made for surgeons to stop blood or other bodily fluids. Furthermore, disposable masks are full of harmful chemical compounds. And last, if you wear a mask and touch it you bring the germs closer to your mouth. And last, if you're not ill you ain't transmittin' nothin'. This is a joke.
Covid is not really airborne in the sense it doesn't float by itself but travels through micro droplets of saliva, which is... (dramatic pause) a bodily fluid!
How on Earth, after a year, you are so ignorant about it?
That was the messaging in the first couple of months, and why social distancing was thought to be sufficient: The droplets would fall to the ground before traveling very far.
Then several months later we started hearing about how the virus can hang in the air for hours in buildings with poor ventilation; that's aerosols, not droplets. At that point social distancing does almost nothing, and even masks are questionable since it can far far more easily go around the edges of any masks, and slip through cloth masks in ways droplets can't.
I am not going to debate my own ignorance, only fact here : you're impolite sir. And you know that most germs are destroyed by oxygen and sunlight ? And the spanish flu backfire was provoked by masks ? And microdroplets fall to the ground they do not levitate in the air ? Do you know about gravity ?
Many people are contagious without realizing it. Some of my own family spread it between each other on Christmas and the spreader wasn't symptomatic until after they had infected others.
The event was within guidelines. And even if you they are assholes that doesn't change the point that you can't say "people who aren't sick don't need to wear masks", since people are unable to self determine if they are sick or not.
And more than that, it's about what's seen by politicians, their constituents, the media, and society at large as effective. Safety theater, as another commenter put it.