I think it's more important where you go through than the actual flight.
Airlines are cleaning, more, but not great, the airports are the question. If you are in a place with a C19 hotspot, remember you are around people who live in that hotspot, but... most of the passengers are passing through. It's once you leave the airport, if in a hot spot.
I flu in June and will again early August, August going out of Denver, not thrilled since they have growing infections, but airport staff are checked, TSA is checked. On the plane you're supposed to wear a mask. In June we were on American and you had to have the mask to get on the plane, once on, many people took them off.