I think the article speaks the truth. Adler has become more flawed in the adaptations and it wasn't necessary.

While yes the original Adler was antagonising the King, there's nothing to suggest she was a serial blackmailer. she'd been linked with many well-to-do men and from that you could suggest she may have done so before but it didn't really matter to the story either way. She had already made her way through life as an opera singer.
In BBC's show,  Adler's 'sole occupation' was intertwined with deceit and lies and blackmailing along with other 'undesirable' events. Why was it necessary to paint her such a tainted image?
And then in the end she wasn't the great mastermind of it all anyway, she needed Moriarty's help. Whilst I wouldn't go so far as to agree with the feminists, she did end up being a bit of a wimp.

Equal to Holmes in intelligence? Well Mofftiss created the character to be so, but I would say not quite. This young Holmes did after all outsmart her in the end.

Nor do I believe that ACD created her to be his equal.
ACD's words tell us that to Holmes, she was the only female that he regarded when he thought of a woman, THE woman. The rest presumably were just the usual female members of society with their feminine flaws etc.
THE woman is not a man, so is not his equal.

In Bohemia, the King (in Holmes' eye) wrongly assumes that Adler is beneath him, not able to marry him and he distrusts her intentions greatly. Once Holmes deals with her, the King then has his eyes opened that Adler is in fact dealing a straight deck after all and all is well in the end even though he doesn't have the picture. He ends up trusting her.
So who really had the worst character out of the 2 of them? As Holmes subtlely pointed out, it was the King who was beneath Adler.

And that tells us where Holmes rated Adler, which was not in any romantic way either.
So possibly not 'equal' as much as 'worthy'.

In "Sherlock" Irene is connected to Moriarty which in the canon of course she isn't. I think that's what makes the whole thing complicated. They could have used the original story without making considerable changes if she had just been a dominatrix blackmailing a member of the Royal Family. But if she had "won", i.e. if she had beaten Sherlock by betraying Mycroft's plans to Moriarty and survived without Sherlock's help, she would have become a very dangerous enemy lurking in the background. And Sherlock would have had to deal with her again which I suppose is not on Moftiss' agenda. 

Yeah, I'm really not so keen on the part at the end where he rescues her...

Many fans think that the very end was not real - that the rescue of Irene was in Sherlock's imagination only - perhaps nothing more than a hold-over from the daring-do pirate fantasties of his childhood (alluded to by Mycroft only moments before that scene).  Personally I have decided to make that my interpretation.  I don't mind her being actually dead.  In BBC version, she was a creature of Moriarty.

Well, the very first time I saw it, I thought that he'd imagined it too. It's just something about the way it's shot, with him staring out of the window as if he's daydreaming.

Canonically the king offers Holmes a considerable reward for (kind of) solving the affair. But Holmes names his price as a photograph of Irene (not the one compromising the king, of course, but the one which she left as a substitute). To me, this is a statement to the king's bad attitude as well as admiration for the woman - and it certainly has a romantic touch to it (or am I to JHW-ish?). 
Moreover also in SCAN the smart, independant woman, who occasionally dresses as a man to live her life as she wants, is forced to accept the help of a man: Norton. It is only after their hasty marriage (with Holmes undercover as the accidental witness - Homes himself loughs at this retrospectively in much the same way as Sherlock does at the end of SiB) that she "wins" by fleeing the country ("run") as a wife.
I would interpret both circumstances as ultimate defeat and also a complete role change - so much to the kneeling and begging, which just reflects the complete role change in her profession in SiB.   
This way SiB works for me and now having reread the original and rewatched SiB, I admire both in many, many new ways. Thanks Mofiss, with many bows.