There have always been people that think they fart sunshine and crap gold, who think that they're above criticism, who think that they're entitled to anything they want and anyone else's considerations are immaterial. That's called ego. History is rife with tales of folks like that, and those are only the successful ones we know about. I don't doubt there've been folks lower on their respective socio-economic ladders who felt just as entitled, but wound up living very bitter lives because they weren't handed all the successes of others. That these people exist is not new.
However, there has been a noted increase in that mentality, at least here in the U.S., with the so-called Millennial Generation (or Generation Y or Generation Next or whatever the en vogue phrase is). Though there aren't firm dates associated with it, we're generally talking about folks born between the mid-1970s and the early 2000s. These are really the first group of people who grew up with computers and digital technology. When I was working at a public University, we were actively encouraged to study these kids because they were becoming more and more prevalent on college campuses. (For the record, I'm just old enough to precede this group. I was eight when my family got an Atari video game system and 11 when I first sat in front of a personal computer, the classic TRS-80. We got a VIC-20 later that year and my father bought one of the original Macintoshes shortly after they came out. Had I been much younger, I would absolutely not have a recollection of not having computers around.)
The Millennials are sometimes called the "Trophy Generation", or "Trophy Kids," a term that reflects the trend in competitive sports, as well as many other aspects of life, where "no one loses" and everyone gets a "Thanks for Participating" trophy and symbolizing a perceived sense of entitlement. It has been reported that this is an issue in corporate environments. Some employers are concerned that Millennials have too great expectations from the workplace and desire to shape their jobs to fit their lives rather than adapt their lives to the workplace.
So what does this have to do with critiquing webcomics?
Well, who's making webcomics? Cartoonists, obviously, but more specifically, cartoonists who grew up with and are comfortable in an online environment. Cartoonists who quickly embrace digital over print. Interestingly, look at the ages of comic strip creators working in traditional newspapers versus those online. There's a split right around age 40 (i.e. being born in 1970); there aren't many newspaper cartoonists under 40 and not many webcomic creators over 40. Those floating right around that age seem to wind up taking more hybrid approaches. That means that most webcomic creators are part of that Millennial Generation. More to the point, webcomic creators are more predisposed to that "Trophy Generation" mindset. That they're out there doing a webcomic is more significant than any level of quality it may or may not have.
Of course, that's NOT to say all webcomic creators have this feeling of entitlement. There are webcomic creators like Phil Foglio (born 1956) working well outside the Gen Y birth dates, and there are webcomic creators like Charlie Trotman (born 1978) who have a less entitled outlook, despite being pretty well within in the Gen Y birth dates. Like any other assessment of an entire generation, it's a broad generality to say they all identify with a "Trophy Kids" label. But I think it does help to explain why there's more defensiveness when it comes to critiquing webcomic creators.
I don't agree with that outlook, personally. I don't think you or I or anyone else is entitled to everything we want, free of criticism. I think it's totally fair to call someone out (myself included) when they're screwing up or doing a half-assed job. And maybe it's just my becoming more curmudgeonly as I get older, but you don't get any sacred cows as far as I'm concerned. I can be polite and I'm not going to out-and-out tell you that you suck, but you have no right to expect my approval just because you're you.
There are a number of collective traits Millennials have that are quite positive. They tend to be more culturally tolerant, more politically active, more socially conscious... More power to them for that! But that doesn't give them a pass for enlarged egos. If they've got a great comic, awesome! If they've got a lousy one, they ought to be doing something else.