It's an admirable attitude to have but sadly only in theory. In practice there's sadly far too much crackpottery on the Internet. That's absolutely fine if the only people reading it are experts who can judge it for themselves, but often that isn't the case. If you are an expert then I agree; don't dismiss something out of hand because it isn't peer reviewed! but if you're one of those people, you don't need to be told that.

To illustrate my point, consider the hoards of climate change deniers, or young earthers out there. To someone who doesn't study the climate or geology, their arguments might sound valid but are actually dangerously misleading. Physics crackpottery is a slightly more intellectual version of that, in that the subject matter isn't accessible to most, but it's no less dangerous. And there's so much of it. So, so much. Some physics bloggers have all but given up the will having battled these people for so long. They're like the conspiracy theorists of the science world. So I feel like it's not unreasonable for a layman to dismiss things out of hand until it's been properly peer reviewed.

We should all be wary of argument to authority, but perhaps less so to argument to experience and mutual respect.