I heard that there is likely to be more than one reason for and or type of, chem trail: population control, weather control, aspect of an advanced 'radar' system. I expect any one, several, or all, could be used at any one time. In UK I notice a type of formation just a few days prior to alleged need for health lockdowns, also there are occasions which easily make weather control seem credible.

I agree. I'm not saying that the only thing they are used for is to make clouds, but if it wasn't for the planes and the stuff they put into the air, I don't know if the earth can make its own clouds anymore? One theory is that they fried the natural weather system when they blew off nukes in the upper atmosphere.