A quick look at Simon Baron Cohen's tweet[1] (linked from the article) shows that this topic seems extremely divisive and inflammatory to people. Is this retraction and resulting modified study seen as an important victory for people promoting that there are no differences between the "male" and "female" brains? [1] https://twitter.com/sbaroncohen/status/832490232721371136
As for the tweet, Baron-Cohen's language in that tweet seems to be a cry of triumph, using language that he presumably realizes (or ought to) would be inflammatory. There are good reasons that this is a sensitive subject. And how you present and talk about the results is a big part of why.
Science--particularly psychology and neuroscience--has a long-established history of unscientific lies and willful misinterpretations about differences due to sex (and race and other things) that have been demonstrably harmful to millions of people. Only the confidence of ultimate privilege could make you think that now we've finally turned a corner and can be totally objective about such things.
When the biggest names in such research lecture other people about how important it is to be serious about studying oh-so-scientific proof of sex differences while simultaneously cheering on their long-preferred outcome like it's a sporting event is... unprofessional at best. A good scientist should be humble about their own instincts and should be thoughtful and careful about succumbing to confirmation bias. But here we had Simon Baron-Cohen crowing over a single result in the most obnoxiously oversimplified way possible.
There's a huge amount of context here that I am (and probably you are) missing, and I certainly can't judge these people's motives. But I'll say it again: serious scientists who really care about finding out the facts about sex differences in brain development should probably not be crowing about single studies on Twitter in inflammatory ways.