It's less wacky politicians (though there undoubtedly are some that actually believe that) and more nationalist propaganda - showing Poland as an island of righteousness against the removed west or something. It's an attempt by the far-right Law and Justice Party to gain support via culture war and shocking people into disgust and hoping they back you based on that. Even at the cost of pretty blatant lies.

It works on my family, at least in part. 😕