Well they do have to make a series of it. I don't think they have harmed the UFO movement very much at all. Matter of fact I didn't know there was a movement. First they say that the ancients could not move rocks that big then they point to Coral Castle where one man did move giant rocks, alledgedly.
I think the question is perfectly valid, "how did they do it?" I think your protest is that they come up with the same conclusion, aliens. Take this for an example. It has been estimated that there are 2.7 million stones placed for the great pyramid.
Calculation of the Number of Stones in the Great Pyramid
It is also estimated that it was built in 20 years, so simple math tells us 2.7million/20 = 135000/ year or 369/ day or 15/hour or one stone about every 4 minutes 24/7 for 20 years. That just seems incredible. But we know they did it, which makes it more incredible.
The damage they may be doing is overexposure. Such as the big foot shows we are seeing. They ALWAYS come up with the same stuff. A bunch of nothing.