Smoking versus chilul Shabbos.
There are plenty of technical differences. Shabbos is a lo sa’aseh and an asei. Smoking is probably only a lo sa’aseh. Shabbos is used as a benchmark, with the example of someone who is mechalel Shabbos befarhesyoh. That distinction is not found in most other areas of aveiroh. Smoking is transgressed in one single manner. Chilul Shabbos has 39 melachos plus many hundreds of toldos, with additional shvusim which are Miderabonon.
I am not getting into the details of the subject. One who is oveir a lo sa’aseh that is Mide’oraysa has violated something very serious. Smoking meets that criterion quite well. Regardless, I was making the point that PBA was grouping all frum doctors as baalei aveiroh. Aside from the factual accuracy of that, I was addressing his choice of the medical field, singling it out from among a vast number of careers. His argument was thus limited to having used accurate grammar, not having sensible content.