I think it's worth pointing out that Cinema Sins and Honest Trailers are very different animals. The first of these, Cinema Sins doesn't really claim to state anything about the overall quality of a film, it's merely listing its 'sins' (and continuity errors definitely fall within that). Honest Trailers, on the other hand, seeks to mock a film's absurdity by using the most absurd representation of it - the action-packed, spoiler-filled trailer.
I was going to say, it is more nitpicking "assholery" (yes that is a word...why do you ask?) as they call it. As has been said, Avengers was torn apart of minor nitpicks that I have seen reviewers analyze in more detail.
*shrugs*
I'm trying really hard to understand how this is detrimental to the film criticism world, other than people on YouTube being snobbish, sarcastic and grumpy towards movies. I think it is more in the public awareness, so maybe that is more of a problem, where there is a larger audience gravitating towards this style of comedy rather than serious analysis. But, like I said before, the majority of people going to see films are not going to give it serious analysis. Heck, I remember walking out of Constantine and wanting to analyze it and my two friends going "Seriously? Can't you just enjoy the movie?"
Edit here: Ok, yes, nitpicking is not a form of criticism that contributes anything more that seeming "looking for problems." I'm trying to figure out how that negates criticism, seeing as how there are still actual critics, who don't nitpick, who present their ideas on different films. I recently discovered another podcast that is an interesting take on film criticism and analysis. I think that CS provides a bit of comedy in what can sometimes can be inaccessible world of film analysis. As much as I enjoy FIYH and other podcasts, there is a level of intimidation to giving a film such criticism. So, you can use CS as a means of thinking about a film in a different way, rather than just a poor form of film analysis.
But, yeah, I'm with John here in that I don't see this type of comedy or nitpicking that bad (or even sinful ). Considering that IMDB has a whole section for goofs on films, and Movie Mistakes has been around to highlight where movies mess up technically, this is not new.
So, when is this depressing episode being recored? If it is Sunday, I will try and be there to make sarcastic comments.