I don't think 41 is old. For me, I wouldn't plan a pregnacy at that age if i already had a child / children.
I think part of the issue with having children older is if you want more than 1 (and don't get multiplies 1st time around) you are tempted to have a very small gap between pregnancies and that in itself is hard on the body at any age. Or if doing IVF, will implant more than one embryo therefore increasing the likelihood of multiples and the known risks that brings to mother and babies.
I am definitely more tired and less fit since turning 40 myself but that's me. I am also pretty worn out by the two children I have so a 3rd pregnancy now would be hard! A first pregnacy at my age might be less so.
I was mid 30s and late 30s for mine, and had fertility issues to get over, so not exactly young or an easy path to motherhood either.
There are those who claim you're never too old to have a baby and that women get treated and judged differently to men. I disagree and think you can be too old. Sure anyone can due anytime at any age but the risks and probability of dying or developing a serious illness like cancer do increase with age - surely that is undisputed?
And however much we drive for gender equality, women (biological women) are the ones who carry a pregnacy and give birth and so carry the risks of those unlike men.
On autism and other developmental and health conditions, there is evidence that older parental age - the father's age especially according to some studies - does affect the chances of a child being affected. I have also seen research which suggests that the risks differ according to family history of autism, for example.
Of course, anything is possible regardless of the age of the parents, and individuals make their own assessments of risk but we can't deny the risks exist. And the lack of support available for raising children with these added challenges is the real issue.