anniebach You say "drinking and having a snort years ago has been brought up in this thread. I question critcising anyone who has done the same (I didn't snort). His infidelities I feel I can criticise."
So, your method of deciding whether someone's conduct might be considered inappropriate is - (a) I have behaved in that way too = I do not express an opinion or (b) I have not behaved in that way = I can make a public judgment.
When someone aspires to take on a very important role, unless their drinking is habitual and excessive and their drug taking current rather than historic, I don't see these issues of much relevance, nor the fact that they have been unfaithful.
However, Johnson has shown himself to be a totally egocentric, dangerously impetuous and unreliable man in both his public and private life. He has a history of behaving disreputably in many ways - planning to have a journalist beaten up, making damaging and ill thought out statements in his role as Foreign Secretary, indulging in several, extremely costly vanity projects in his role as London Mayor and completely reversing some of the promises made before election to that role.
His intimate and family relationships appear to have been conducted in an equally irresponsible and chaotic way.
Not a great cv for the post of Prime Minister, but it seems that as long as he is considered "a bit of a character", "entertaining", "charismatic", etc, etc, that is enough for some voters.