SCOTS director Lynne Ramsay is at the centre of a row over sexism in Hollywood after she walked out on the $15 million-budget Western she was due to direct, sparking a debate on the film industry's attitude to female directors.

The filmmaker sent shockwaves through Tinseltown last week when it emerged she had failed to turn up for the first day of shooting on Jane Got A Gun and was replaced 24 hours later by US director Gavin O'Connor – to the surprise of stars Natalie Portman (who is also a producer) and Jude Law. Law, who had signed up on condition of working with Ramsay, quit the next day.

News of the We Need To Talk About Kevin director's sudden departure provoked a slew of misogynistic comments online, describing Ramsay as "hysterical", "ungrateful" throwing a "hissy fit", "emotional", and "P.M.S.ing".

One commentator accused Ramsay, 43, of "setting female directors back 20 years". Another dubbed her a "prima donna".

Sasha Stone, founder of the Hollywood news websites Oscarwatch and Awardsdaily.com, said it seemed as if commentators were trying to "verbally stone" powerful women in the film industry "to make sure another strong woman never emerges in Hollywood again".

And she criticised "the whispers and moans of people who have nothing better to do than to hate on some of the industry's most promising female writer/directors".

The original story, broken on Tuesday by Deadline Hollywood reporter Mike Fleming, hinted at a breakdown in relations between Ramsay and the film's producer-financier, Scott Steindorff.

Fleming wrote: "A lot of filmmakers step off projects and we chalk it up to creative differences, but I can't remember a situation when a filmmaker who developed a film didn't show up for work on the day it starts production. Clearly there was drama the weekend before, but this is pretty shocking."

Fleming was criticised for his use of the term "drama" with commentators saying it would not be applied if a male director had been at the helm.

Calum Marsh, writing on review site Film.com, said: "Whatever the reason [for Ramsay quitting] proves to be is irrelevant to the overall tenor of the reportage, not to mention the content of much of the online backlash.

"Tony Kaye not only missed the first day when filming the project Marlon Brando hired him to direct, he missed several days before being unceremoniously fired. Though nobody, as far as I can recall, described his behaviour as hysterical or his actions as caused by 'drama'."

Meanwhile, Ryan Adams, a journalist on Awardsdaily.com, said: "The default mode on male-dominated comment pages I've seen is to find a way to finger the female ego as the unstable element at fault. Whatever the actual problems may be, the worst idle chatter today revolves around Lynne Ramsay being a woman and reckless speculation about how this mess might damage or wreck her career."

Ramsay has yet to speak publicly about how the project unravelled.

Steindorff told Deadline Hollywood Ramsay's conduct had been "irresponsible". He added: "It is insane somebody would do this to other people. I feel more for the crew and their families, but we are keeping the show going on."

Subsequent reports have shed light on what appears to have been an ongoing power struggle between Ramsay and Steindorff about who had ultimate creative control. Ramsay would reportedly have lost the rights over the final cut if the project – already beset by delays and last-minute cast changes – went over budget. She is said to have resigned last weekend after producers refused to discuss amending her contract in light of the delays.

Other reports claimed she was frustrated at the lack of an approved schedule, script or budget for the film with just days to do before shooting – while contradictory accounts claimed the Scot was revising the screenplay but had "failed to deliver a shooting script despite several delays and increasingly bizarre behaviour".

An article in the Hollywood Reporter noted: "Sources who have worked with Ramsay say that the director can be fickle and difficult. But her defenders respond that such characteristics are common among top filmmakers and that Ramsay has been painted as particularly difficult because she is a woman."

Indeed, directors such as Stanley Kubrick, Martin Scorsese and David Lynch are more likely to be described as perfectionists, obsessives, or eccentrics.