This doctor also states that a COVID-19 particle is too small to be captured by even an N95 mask. Is this missing the point about filtering out fomites?

Here again, he is taking a very narrow circumstance and making a sweeping generalization. Many times the disease is transmitted through fomites generated from acts of coughing during which large globules of moisture are expelled which contain the much smaller virus particles. These are readily filtered out by wearing a face mask and a face shield as well as further protection from eye exposure. It is true that aerosolized virus with drying of the droplets results in extremely tiny particles that may or may not end up on a mask of N95 grade or pass directly through and be inhaled. But just because a barrier to spreading the virus is not 100% effective, does that mean it should be used 0% of the time? It is the same with hand washing. Many times it is helpful and occasionally it is not done adequately to remove all virus present, but no one would suggest abandoning hygiene practices simply because they are not 100% effective. Again, this is a disservice to spread such ideas. It is better to make clear why mask use is important but also caution people that it is not an absolute guarantee so they can weigh the risks and benefits of entering into a public place where others are present, especially if there are disease sufferers known to be in the location.