Regarding windtowers causing cancer - I doubt it. Technically, full quote of Trump reveals he said: "They say" that windmills cause cancer. Don't take anything he says literally.

Do windtowers kill birds? Yes, and kill bats. But not in huge numbers. They don't rotate that fast.

The real objection to windtowers is this: Once the total cost of creation (mining, manufacturing), transport, setup, road access, powerlines, security, etc. is factored in, and then operational cost - the wind tower runs at a net loss over total lifetime cost of ownership. It is only because it is subsidized by the federal government via tax credits that it makes any money at all. Drop the federal tax credits, and wind towers would not be deployed except for rare "off the grid" needs