The public demands that Something must be Done. The TSA is Something, therefore it is Done.
I personally assign blame straight on the general public. The general public is a bunch of scared nitwits who can't stand any possibility of any risk when flying on an airliner, even though they literally stand a higher chance of dying on their trip to the airport than on their flight. This irrationally frightened public demands that their elected officials protect them from the imaginary monsters under their figurative beds. Government simply complies with their wishes.
I don't know anyone in the general public you describe. I know a bunch of people wondering what the hell is going, or worse, don't care.
In fact, the only place I've heard of the "general public" proclaiming "something must be done" is in the media. But the media isn't the actual general public.
I see parents lobbying to remove playground equipment that causes occasional scrapes, I see a proliferation of ridiculous warning signs, I see people freak out deeply and in large number over a heavily trafficked "dangerous intersection" that's seen one crash, non-fatal, in years.
People don't seem to like the TSA in general, but they like it more than not having it.
I believe this may be a vocal minority. Just like all of the "children aren't allowed to pray on their own in schools because it might make another student uncomfortable" people. I doubt that a large portion of the population even cares, but a couple of vocal people and a lawsuit makes it a political hot-topic.
They are scared nitwits, but only because they don't demand that the government's unprecedented expansion of surveillance be stopped and reversed. The TSA is, for the most part, despised by anyone travelling. On top of making you show up hours earlier than you would have, they grope you. No one demands that.
I personally assign blame straight on the general public. The general public is a bunch of scared nitwits who can't stand any possibility of any risk when flying on an airliner, even though they literally stand a higher chance of dying on their trip to the airport than on their flight. This irrationally frightened public demands that their elected officials protect them from the imaginary monsters under their figurative beds. Government simply complies with their wishes.