Yes, but the phenomenon occurs at specific altitudes, so you just fly slightly higher or lower.

They are, but clouds disproportionately reflect IR. Basically the energy comes in as a mix of high, medium and low energy light. The earth re-radiates as low energy IR. Clouds trap this keeping the warmth (and energy) in.

Clouds and CO2 act in a similar way.

Current scientific consensus is that contrails are a net contributor to warming (they trap more heat from escaping the atmosphere than they prevent from entering overall) - but it's a complex phenomena that's difficult to model, so studies vary a lot in estimating the magnitude of this effect - from being a fraction of airplane CO2 emissions, to being several time that.

This isn't someone guessing, man. He's citing research on the topic.

Essentially, these clouds are 50% opacity to visible light, but nearly 100% in infrared. So they block some incoming light, but reflect almost all infrared from the surface. It's a net warming effect at these altitudes.