I think there is a problem with breastfeeding in that many women are led to believe that they can't, or put through such stress and shitty treatment thanks to poor advice/too much pressure/combo of pressure plus bad support/info that they can't go on any more (and who would blame them) or in many cases given info which leads to their milk supply reducing or their discomfort/pain increasing. And actually, given the correct support and/or info, whether in response to problems or whether they'd had access to it from the start and avoided problems, they might have been able to breastfeed and/or had a much nicer, less painful, easier, less stressful experience.
And I do think some of this comes from formula companies' marketing and I do think some of it comes from living in a FF culture. It's not just one advert or website quiz or being sent a voucher in the post - I don't think that those single things disrupt breastfeeding, it's a combination of everything. When good support and information is not freely accessible, these other sources take over. The first thing people usually do these days is google something - and an article on a popular baby website sponsored by a formula manufacturer is likely to have a higher rating on google than something by a well evidenced breastfeeding support group. Formula companies have recognised that breastfeeding mothers who are struggling feel unsupported and so they develop a very cuddly, caring, nurturing sort of profile - in various guises. Aptamil's approach is "We know it's hard, so don't worry, come to our science and precision, we're not really like those other formulas". Cow and Gate's marketing is quite defensive, emphasising a kind of "fed is best" mantra and offering various cute products like cuddly toys and personalised books, SMA's marketing emphasises the benefits of FF - let Dad help, take a break, you're doing great.
If you don't google - you will ask your midwife, GP or health visitor. It's logical to go to these sources first. And yet if their training is poor, nonexistent and/or they have received aggressive marketing from formula companies, they are likely to give misleading advice/info. Sometimes it is simply wrong - I have heard so many women say that a midwife or health visitor told them a latch was "fine" when you cannot tell this only by looking, sometimes people have set ideas about timing or positioning or sleep safety and tell a woman that something she is doing is wrong, when it was working for her. Quite often the bare minimum of care is given - treatment for mastitis without any follow up support to work out why it happened in the first place, sticking-plaster solutions such as nipple shields or top up feeds (expressed or formula) with no long term follow up plan - whether that's poor training or lack of time/resources, I don't know. As stated earlier, they usually don't have awareness of all of the avenues of breastfeeding support available since these are mainly run by breastfeeding support organisations which are totally separate from NHS care. So people can hit a brick wall here.
Or you may ask family and friends. And if they happen to be well informed/experienced then you may get good info - but if they have the norms of a bottle feeding culture in mind then they are likely to have expectations which are not compatible with breastfeeding, such as babies having discrete and evenly spread feeding times, or breasts needing to be very full before a feed and that feeling empty means there isn't milk there, or ideas which might be unhelpful such as maybe your diet is poor, or suggestions like letting somebody give a bottle to give mum a break, which might well be fine, but it might be more beneficial to give her a break in other ways, especially if she ends up expressing and dealing with the cleaning and storage of the milk/bottle in order to facilitate this "break".
I understand this is an unpopular suggestion because saying that many women who stop breastfeeding could have continued given the correct information and support is often misconstrued as meaning that the woman did not try hard enough, should have magically been able to ascertain what is good info over bad, didn't read enough, didn't push through difficulties, whatever. Or invalidating her experience. I don't believe that at all. I actually think it's awful that new mums are left to navigate this alone. Nobody is born knowing how to breastfeed, we learn it from cues in our culture (other animals do, too - animals raised away from other nursing mothers tend to have more problems nursing their young) and then like everything else, we learn from physically doing it and trial and error - but if the main options we are being presented to trial result in error, it's less likely we will come across options which lead to success.
We could counter this (IMO) by including the physiological process of breastfeeding in the national curriculum as part of reproduction and human biology - that would give most people a baseline understanding of how milk production works, which may help avoid some of the myths people believe about BF.
Then either good training and info for front line HCPs and/or a lesser role in PCTs for a breastfeeding specialist who is actually trained in accordance with high standards - I know some areas have these specialists but their training seems to be hit and miss. Or for front line HCPs to be able to work with voluntary and other organisations and refer women to these experienced helpers - with a disclaimer about it not being NHS sanctioned, if you like. But at the moment women have a huge battle in front of them to find the support let alone access it. Are somehow expected to sort out good info from bad in a subject they have no existing knowledge in, and are then treated unsympathetically by people who are meant to support. No wonder we find breastfeeding really hard and challenging - in the UK at the present time it is absolutely not the case that 90%+ of women can breastfeed successfully, but it's not their fault.