Its easy to disagree with much of the opinion in the article. Starting with Gatsby, which didnt really blow anyone away, got mediocre reviews and only slightly surpassed expectations ($45 million to $50 million was the prediction, and it made $51 million). Perhaps they took a small percentage of the female audience, the ones that would have made the opening hit $90 million, but its not really huge. Also if it holds to pattern and with the Memorial day weekend, we're looking at another $40 million+ next weekend, plus whatever it makes during the week, possibly pushing up the total to $140-150 million in 12 days. Its not a bad total at all.
The Forbes article has some interesting observations but Forbes is selling this week's potential grosses very short. Given the film has performed in line with Trek 2009 there's no reason not to expect it the perform similarly during the week bringing in $25-28 million Mon-Thurs, and next weekend the film will certainly make some $40+ over the four day weekend giving it a total close to $150, again on par with Trek 2009.
I think waaaaay too much is being made of this last minute $100 million estimate.