She was so f-ing hot in Eurotrip. It's hard to imagine that she ever got fat. But it happens to the best of us.

I definitely see what you're saying - and, yeah, she never cemented ina24to the film industry.
However, given where she's currently at right now, her weight is holding her back.
You can't deny that she'd at least be getting offered beep early 30s female characters in films. I could see her getting offered Mike and Dave Need Wedding Dates in, like, Plaza's role had she been thinner and more marketable. After all, she was just seen alongside Efron in 2009's 17 Again. Her options and every other actress's options constricted with added weight and when they're older, if they're not already established.

But the timeline on her fading career doesn't quite agree with your claim of it coming down to weight. Her career dropped off as far back as 2010-2011 (once Mercy was cancelled), with her the only major active thing for her being continued roles on GG, which was slipping in the ratings by that point. This happened well before her weight changed, and so my argument is that Hollywood had little use for her talents regardless of her weight.
As a partial explanation, I don't think you can ever discount the vocal, bitter, and delusional contingent of Buffy fans out there who blamed the later years changes entirely on her and continued to claim she 'ruined' GG just like she 'ruined' Buffy.
In 2013 she was nearly nominated for an Emmy in her Russian speaking role as Oswald's wife in Killing Kennedy (at least several media types had her making the nomination list). If she had been nominated, all it would have taken was subsequent media hype pointing out the willingness of her to do a non-English role and the roles could have built up for her again. She's been unlucky throughout her career (scheduling conflicts preventing starring in roles in Freaky Friday and Twilight) but hopefully that luck will change for her one day.
I just don't think (and certainly hope), it doesn't come down to weight for her. Because she's lovely the way she is, and Hollywood needs to loosen up on its obsessive standards.

I think she's wonderfully talented. I also don't think she should be defined as a television actress because she did quite a good amount of films in the 2000s. I think it's a combination of two things: a.) she's taken a lot of time off from film/tv since Gossip Girl; b.) she's gained some weight. But it all most certainly stems from the last part.
She is by no means unattractive, but by Hollywood standards, she's not thin anymore. When you're not already super famous or on the jet-stream with your career, a weight problem can push you out of the limelight. She would likely be offered more auditions and placements in film/tv as a 30-year-old if she fit the mold of what successful 30-year-old women look like in Hollywood. She doesn't look like that anymore and she never stabilized enough in the industry to have her talent overcome the weight issue. Thus, she has faded.
But I hope she comes back because she is a joy.

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She hasn't filmed anything new this year! Last thing she filmed was Sister Cities about a year ago and that still hasn't come out. I think it's fair to say her career has stalled badly.

I've wondered the same thing I thought that after Buffy she would go on to better things but her career stalled.
Libera te tu temet ex inferis.
pro ego sum diabolus, pro ego sum nex.

Its a waste - but it will be over soon.
That sounds ominous
Film biz where thieves,pimps run free,good men die like dogs.There is also a negative side.

Its a waste - but it will be over soon.
A gentleman will not insult me, and no man not a gentleman can insult me.

Promoting Hillary Clinton is her career now.

Those two facts aren't mutually exclusive. According to this little blurb
http://wwd.com/runway/fall-ready-to-wear-2015/new-york/naeem-khan/fashion-scoops/
she has been in meetings to get something she wrote filmed for at least a year now.
She just received her first production credit on Guidance. Hopefully her luck turns on a writing credit soon.

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She's a tv actress, mostly.
You compare her with movie actresses.
Also she's a writer, on top of all. Thats a career that can last her lifetime.
You shall have no other Kates before Kate Winslet.

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Her career did take off. Much like the Wright brothers first flight, it then landed a short distance later
LOL
If Ari Gold saw Chappie he would say:
"Chappie makes Elysium look like Citizen vcking Kane"

Her career did take off. Much like the Wright brothers first flight, it then landed a short distance later.

Like any job it comes down to a number of things. How much work she wants to do, how good her agent is, how much money she's asking for, how impressed the industry is with her work (they're 1000x more knowledgeable than you or I about this kinda thing), how she behaves off screen, how far she wants to travel for work, how professionally she handles herself, how good her auditions are, etc. Could be any one of a whole bunch of things. I loved her in EuroTrip, although I doubt that's the sort of film that would be high up anyone's CV.

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I have to agree it is more luck than anything. I remember reading somewhere (don't remember where) she had been in the running for Bella Swan in Twilight. Of course as we all know the role went to Kristen Stewart instead. But can you imagine what would have happened to her career if Michelle had been cast instead.

I dont think fanatic Buffy fans has any part in that. Its a small group of people that. But agree with luck she not the only one not making it big. Its a few that 5b4make it and its a matter of winning on the lottery kind of thing. Getting that one role that changes everything.

I think part of the issue was always the very negative reaction many Buffy fans had to her most recognizable role. Some of them never shut up about how much they hated Dawn, and by extension, Michelle. Plus luck can never be underestimated in actresses making it big, if that is what she actually wanted, some of her interviews suggest she never did. She still looks very young, so there is plenty of time for a breakout role yet, assuming a breakout role is possible for a woman not nearly as thin as the other actresses you named.

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