It is interesting because my personal experience does actually support some of these theories even though I disagree with them on an emotional level.
Because I knew that we have higher chances of miscarriage I have not yet thought of any of mine and DH's three pregnancies as being a baby. I haven't pinned down a concrete due date and although I've joined in conversations e.g. on mumsnet about the due month, I've only really thought about it as a potential pregnancy.
With our first one, DH got really excited and wanted to go and look around baby shops, talk about names, he announced to family, etc. This I was all OK with, but he was totally crushed when we lost the first one, and refused to do any of that with the second, which we lost again. Now we have our third he has started to do this but after we've got past the point we lost at before. I'm feeling more hopeful for this one, but still don't really think of it as an actual baby, and I don't know when that will happen. I am a little bit anxious at this sudden change and wonder if we lose this one a little later on whether it's going to be as hard for him as the first, or even worse.
Although obviously I've been upset by both of our losses, it's been more the lost pregnancy to me than a lost baby, the frustration at the lost time and chance more than anything else. The due dates didn't bother me when they came around and I see it as a matter of fact thing, I even find that other people's sympathy is more upsetting to me. So for me, this idea of not being heavily invested, not thinking of it as a "baby", has helped me to cope better - but I just can't support this as blanket advice. I'll happily explain that it worked for me if somebody is asking, but I'd never expect everyone to be the same. Partly because I think this is just my personality - I'm always optimistic anyway so it helps for me to put a downer on myself to keep my optimism in check and doesn't depress me. The problem isn't on my side, so it's not something I can take personally, which I know is incredibly hard for a lot of women struggling with repeated miscarriage. I think that some people struggle more with negative thoughts and can get themselves into a really low mood when trying hard not to be positive and so for them, positive thinking is more helpful. People are just different - and I absolutely don't think I've got it "sussed" or that my reaction is any better or more right than somebody else's. I would much rather that somebody like me is given support and sympathy they don't need, than that someone who really needs the sympathy is treated coldly. I don't know how I will react to any potential miscarriage in the future - if I do have more, I might find them harder, or just react in a different way.
It is not snowflakey at all to experience sadness, and loss, and grief about the loss of a much-wanted pregnancy (or even a surprise one!) whatever stage it happens at. It's also not strong or smart or unfeeling not to be very upset by it - it's just a different reaction to a different situation.