I know strong opinions tend to be popular online, but I hope comments like this don't discourage people from learning and going out there. The books and internet are more than enough to stay safe.
As a random aside, a crap-ton of flowers are toxic. Flowers. If somebody hadn't told me that, I'd be eating random ones I find on hikes, because I heard of edible flowers and for some dumb reason I thought they all were.
It depends on the intentions of the site. If the author is advertising it as a complete guide, then I agree with you: it's incomplete as a guide. If he's advertising it as a starting point -- start with these mushrooms which have a very low risk of harm -- then it's fine in my view.