I agree with what he has to say entirely. It's annoying that people judge you based on a belief or think that you are imposing it on them in some way just because you have the belief and are keeping quiet about it.
For instance, I have never really drank much in my life. In my 18-24 age range my doctors told me not to drink because of something weird with my body (it's complicated). Okay, I'll do that or I'll die, sounds pretty straightforward and not that hard. People would ask me at parties if I wanted a drink, and they'd come back with hate towards me and avoid me like the plague like I was judging them. I wasn't, I had a legitimate health condition.
That being said, the reason people feel this way is that there ARE people like this:
(replace gluten with whatever, alcohol drinking, veganism, atheism, christianity, whatever)
So yes there are people who are quietly trying to live their life the way they want, and get judged when asked about it. But likely, it's because people just assume you are in that "group" of those other people that pester the shit out of them for what they do. For instance, I eventually got asked a bit more by a couple of people why I didn't drink, told them it was because of a specific health condition, and they ended up becoming friends of mine. I later found out that they, even though they would drink maybe 1-2 beers a week, were getting constantly judged by their parents about "alcohol is bad, you should never drink alcohol!", and likely it's true for most people like that.
I also have known people who preach their gluten intolerance at every chance they get the same way as in that video, vegans who scream bloody murder when you eat meat around them, etc.
The problem isn't that one side is bad and one side is good, it's that people identify people in terms of their groups. Either themselves (I'm an american! I'm black! Sister solidarity! Go Red Sox! etc), or others (he's vegan, he's black, she's a woman, he's a muslim). So everything anything that people do who are a part of that group gets tagged as something the whole group likely does (which is where racial/religion intolerance comes from, and why muslims are hated by a lot of westerners because they group ISIL/al-Qaeda with the Koran).
It's just a way to filter out large amounts of information/people because there is just SO FREAKING MUCH OF IT now. With the internet we have access to so many ideas, and the population is really ridiculously high. How does the human brain account for that? Filtering by group.
The problem is that people don't realize this is happening, it's mostly subconscious, and they don't reflect on themselves. So when a christian hates all muslims, they don't think about the chrisitian neo-nazis trying to murder all black people, they think of themselves as a full representation of their cause.
And the rest of the people who don't think this way end up just blind followers, and fall into the groupthink. So a massive ego will lead a cause, spell out a course of hatred toward another group, then all of his followers just fall in line.