When you said this:
I actually don't care if I'm being judgy. I still don't like it and still see no need for it.
Even for a child who won't settle/has reflux.
Use a sling, buy a pram that can be used from birth and have the seat every so slightly reclined (like the out n about nipper, or bugaboo bee)
You REALLY REALLY were BU.
DS was great in his pram. He didn't have reflux.
If he had, I'd have done what I could to cope though. Because me coping is an important as the small risk that a car carrier might provide. You have to balance the risks posed by your circumstances. Therefore, it might not be ideal, but if it stops you having other problems to deal with or prevents harm to you (which in turn have an impact to your baby and are not mutually exclusive issues).
DS would NOT go in a sling. I bought one. Tried one. Repeatedly. It was not happening. How are you supposed to use on, if you have a child who gets very distressed in one? Is that good for them?
As for buying a pram that can be used from birth so the seat can be reclined. Errrr one there is the issue of who buys the pram (I know a lot of well meaning grandparents who do as its an expensive purchase as parents struggle to find the money for a full travel system), or buy a system with good intensions to use the pram and then find it inappropriate for their child. Are they supposed to then buy ANOTHER system. The fact you suggest the Bugaboo bee really shows you are aware with the fairies! It was beyond my budget at the time, and we dismissed it was it wasn't suitable for us for other reasons.
The pushchair bit of my system which could be reclined was not supposed to be used until the child could hold their head without support which is another issue entirely. This wasn't a problem for DS but he was so small and skinny we had other problems. We had a gap of 2 months where he outgrew the pram but was too small to be strapped into the pushchair safely. We ended up merely carrying him between the two of us when out during that period, but that is not practical or possible for most people, so if the car carrier worked, then fair enough.
I don't care if you don't mind being judgy. You are ridiculous and narrowminded and obviously have more money than sense. This should be pointed out, not for your benefit but in case anyone reading this is upset because they are struggling and is just trying to do the best they can. Being judgy has an impact on other people. Its massively selfish and can be massively damaging to the well being of others.