The CDC itself at one point proclaimed that masks were ineffective and possibly even counterproductive, so it's not just "some guy." The logic there was that cloth masks do very very little to stop viral aerosols, and on top of that, long durations of wearing them turn them into a warm, moist cover over your face, an environment that viruses love. Plus, unless you regularly clean them, the masks themselves turn into disgusting microbiomes.

Then the idea was that wearing any mask prevents you from spreading droplets, and so it was a good idea.

But covid is, of course, primarily spread through aerosols, which are going to essentially ignore anything below an N95+

There are arguments to be had about the dispersion of aerosols when the wearer is/isn't wearing a mask, but at the end of the day the fact that we don't asphyxiate on our own CO2 means that the air and aerosols are circulating pretty effectively, regardless of wearing masks.

As far as protecting yourself goes, cloth masks aren't going to do anything significant for you.

But, of course, the entire topic is so highly politicized now that you're unlikely to get an unbiased answer from anyone