They've become a part of her character. Accept it and move on.
http://www.nintendoworldreport.com/blog/27357
You rarely hear cries from the readers, much less the artists and writers, that Power Girl’s characteristic bust be toned down or that her trademark “cleavage window” be closed. It’s not often you read magazine articles in Entertainment Weekly or TV Guide bemoaning Sofia Vergara’s wardrobe on Modern Family. But people always get bent out of shape about poor Lara Croft. When Crystal Dynamics thankfully took over the franchise from Core Design in 2003, they spent three years crafting Tomb Raider Legend, and one of their bullet points while redesigning her character was to tone down her most mammalian organs, that which had been partially responsible for her success and infamy as a character. This was a priority—the thinking was that by making Lara more realistic, she’d be more relatable, and more people would buy the game. Legend was a success, but probably not because of Lara’s breast reduction—more likely because the game was actually good.
Crystal Dynamics claims they shored up Lara's assets for TR: Legend, then proceeded to show as much of those assets as possible. Compromise noted.
The follow-up to Legend, Tomb Raider Anniversary, restored Lara’s endowments and even added some subtle visual jiggle, something we hadn’t seen yet in a Tomb Raider game. However, unlike the previous game, Lara wore no split evening gowns or cleavage-baring tops. Instead, her wardrobe choices seem purposefully conservative. You might say these factors cancel each other out, but the aftermath of this decision is unclear—I don’t remember anybody bitching and whining that Lara was once again able to comfortably fill her bra, but Crystal Dynamics must have been unhappy with the direction Lara was going (again) because they covered her up entirely in 2009’s Tomb Raider Underworld. In fact, I might suggest that Lara’s costumes in that game actually downplay her chest. If Crystal Dynamics was going for realism, I applaud them while also pointing out that there’s nothing realistic about a 30-something Lara Croft plowing her motorcycle through ancient subterranean ruins while battling giant albino spiders and undead warriors. Tomb Raider has never been realistic—it’s a cartoon.
There was a Wii version, as you'll recall. This is Lara's normal outfit in the game, and also the one that shows off the subtle jiggle effects. Again, kind of a contradiction.
More confusing still, Crystal Dynamics actually reneged on their “more realistic” Lara with Xbox 360 DLC. The downloadable level “Beneath the Ashes” includes not only a fairly simplistic new area, but also several new costumes for Lady Croft, including three or four revealing bikinis in different colors. One might say this was the developer apologizing for the main game’s complete lack of cleavage, or caving to the Croft purists, while simultaneously revealing an inherent contradiction in their design philosophy: to titillate or not to titillate? That is the question, and it’s one Crystal Dynamics can’t seem to decide on.
You'd think Lara's V-neck top would show some cleavage, but it really doesn't. This is puzzling.
It would appear Crystal Dynamics is once more rebooting Lara’s adventures. Fresh out of her Alma Mater, Lara will be shipwrecked on an island, suffering grievous injuries in the process, and will have to find food, supplies, and help during her stay. Her character model has changed considerably, almost to the point of not really looking like Lara Croft anymore. The ponytail is gone. The sharp eyes and calm demeanor have been replaced by a disposition much more panicky. She’s wearing cargo pants. Her breasts really are significantly smaller, more “realistic,” you might say. And maybe this is fine for what they’re trying to accomplish—gritty realism, island survival, and lots of bandage application. But you’re taking away everything that’s made Lara, well, Lara for the last fifteen years.
I love it, sure, but it muddies Crystal Dynamics' intent with the character, doesn't it?
Lara Croft has a ponytail. She’s cool under pressure and happy to leap around stone-age citadels. She wears ass-hugging shorts and she has a big rack. It’s not Mai Shiranui big, it’s just big. And you know what? That’s okay, because there are plenty of real-life women with big breasts. I married one. The internet is filled with them. They exist. Western game developers need to stop apologizing for giving their heroines attractive assets. Should male gamers start ballyhooing over Nathan Drake’s chiseled good looks, or Kratos’ sculpted abs? Physical features are part of what make a character recognizable and iconic. Lara has her ponytail, short shorts, and bosomy bosom. Crystal Dynamics needs to get over that and recognize the sad fact that their new Tomb Raider game could be a completely new IP and nobody would know the difference. Once you take away everything you helped Lara become over the last five years, that character ceases to be Lara Croft.
Notice that in the Batman reboot, Bruce didn't start wearing anything other than the batsuit.