The notion that 7 Billion people in the world are living under a 'Mask Policy' which have no material value, but exists only for the purposes of 'signalling' is conspiratorial nonsense.
At the start of the pandemic, the efficacy of masks in the commons was still debatable, more so than is now.
Public Health Policy issues around getting 100's of millions of Westerners, not acclimated to wearing masks (as they are in some Asian countries), was a daunting concern, as we can see with all the anti-mask idiots even to this day.
N95s in particular were acutely necessary in Healthcare settings and the supply chains from China towards the start of the pandemic in the US were not quite ramped-up, and were just becoming secure by the time the CDC switched to a pro-mask footing. Otherwise, any call by the CDC for 350M Americans to 'wear masks' would have likely overran the Healthcare supply chain.
As the availability of PPE to Healthcare became secure, as Asian health officials urged Westerners to adopt mask policies, as we understand a bit more about masks, the policy shifted towards mask wearing.
Obviously, masks are a marginal tactic in the fight against COVID, but there is a systematic benefit, especially over 350M people million people, wearing them when they are interacting wit others. If there is ambiguity in their efficacy, it's rational to err on the side of caution, not the other way. Because we are 'going with the policy' then it has to be supported and enforced, like anything else.