the attempt of someone who is far to the left side in hashkofo and in bein odom lemakoim to show off what a “tzaddik” he is in bein odom lechavyro
That may be your suspicion, but it’s not based on anything. I think it’s unfair to assume, and certainly to post.
Fear of chillul Hashem is, or at least should be, universal across the entire spectrum of frum society, and there’s no reason to assume lack of sincerity regardless of other hashkafos.