I think there's a reasonable argument for the effectiveness of M95+ masks worn in limited contact situations, either outdoors or spacious indoor areas, without ever being removed, only when worn properly.
As soon as you start adding in "extended contact" or "small indoors areas" or "removed to eat" or "fidget with mask or don't have sealed sides", they rapidly approach the point of being totally fucking pointless
As I've said before, we're immersed in a fluid medium. Whether its aerosols or even small moisture particles, air currents are enough to disperse and thus immerse people enough that anything more than fleeting exposure quickly becomes enough to be infectious. If two people are breathing air in the same room for any significant amount of time, they are already exposing each other to covid. Even if a mask blocks 95% of particles, the other 5% become enough when the air is thick with cooties. When people have any means for air to flow around a mask, whether removed even briefly or worn improperly, that's going to make it similarly pointless.
We've had 2 years of real world application and there's been dick all correlation between covid outcomes and the populace's mask wearing habits. States with mask mandates and widespread mask usage were just as affected by geographically clustered covid waves as their anti-mask neighboring states. And geographical is the operative word, because these waves have spread with little relation to demographics or politics or prevention measures, and instead been trends of peaks and valleys associated with alternating sections of the country. Right now its the east coast getting hammered despite heavy vaccination and mask wearing, while the west coast lagged behind by weeks and is only picking up on the omicron wave this week.
Loosely fitting cloth masks do nothing and even the CDC admits it. That's been plain since the start. I don't think M95s are showing much practical effectiveness, but at least they've got some argument in the right circumstances, but more often also do nothing.
The CDC has given us a lot of really bad advice throughout this pandemic and been wrong more often than they've been right.