It should also be noted that PMQs are a "pressure release valve" for British politics. If you turn on BBC Parliament at any other time outside of that 30 minute period it is all very serious, very respectful, and a lot is accomplished.
I had BBC Parliament on almost the entire day during the "Gay Marriage" debates, and to be frank it was some of the best political discourse I've ever seen. Even though some people took the topic personally (e.g. old religious conservatives) they were always extremely respectful to both gay people AND to other members.
Keep in mind that debate was not whipped. So it made for quite an interesting dynamic with conservative debating other conservatives and some labour people coming out against gay marriage.
That said, any politician interrupting with "you lie" as in the example the original article provides for contrast would rapidly find themselves directed in a schoolmasterly manner by Mr Speaker to withdraw their words and apologise for their "unparliamentary" behaviour.
e.g. https://www.youtube.com/watch?v=89S1cej9TyUhttps://www.youtube.com/watch?v=i9hrfc40Lko
I doubt any Brits would consider politician's jibes - especially the scripted ones - a high point of our humour. The best thing that can be said for the schoolboy humour of Opposition questions in PMQs is that it represents a welcome break from the dreadful toadyism of questions planted by government backbenchers.
I saw 'The Day Today, Episode 1: Main News Attack' in the YoutUbe sidebar of your linked videos, well worth sharing as a staple, neigh bedrock, of 1990s UK satire that Iannucci, mentioned in the original article, was also heavily involved in.
https://www.youtube.com/watch?v=b1iL2jGZiZw https://www.youtube.com/watch?v=uUqhqsfE0YQ https://www.youtube.com/watch?v=MVs1jN85w10 https://www.youtube.com/watch?v=mUX9LvYlAps