Never fully bought the landing strip idea tbh. The lines are on a plateau with massive rocks and uneven ground, nothing's actually landing on that surface. Erich von Daniken did a real number on people with that one.
That said I don't think the theory is completely dead in the public imagination, it keeps getting recycled on every ancient aliens documentary going.
What I find more interesting is the water/ritual procession angle that the proper researchers have been pushing. Some of the animal geoglyphs line up with seasonal water sources which makes way more sense for a desert culture. Took some aerial shots of similar earthworks in the Dales last year and even from a low altitude you can see how these things are clearly meant to be walked as much as viewed.
Anyone else looked into the acoustic properties research? Apparently some of the lines have unusual sound resonance. That's the bit that's got me lately.