That's all good OP but what about the trails at altitudes of 10,000 feet or less? Not cold enough there to make ice crystals. Plus contrails don't start and stop abruptly and hang in the sky for hours and hours spreading out for miles.
Your ignorance of technology should embarass you. I personally have witnessed jets at very low altitudes, 6000 feet, spraying an obvious chemical trail, then abruptly turn that mechanism off.

Also i know two commercial airline pilots whom I've asked about this phenomenon. One refused to talk about it and the other said 'i don't know what THEY are doing'. One flies for SW and the other for United.

And the University of Arizona chartered a plane, went up and took air samples inside of a contrail, and measured aluminum and barium particles that don't just magically exist in our atmosphere. Their work is thoroughly documented.

So i guess you can gag on my peter whenever you are ready.