The reality is IVF treatements are expensive, I belive around $15,000 a try and they are only about 20% successful.
We could easily be spending $60K or more per kid.
While its a great thing for this for more kids funds are not unlimitted
Lets say we pay for 1000 treatments that 15 Million dollar, that 15 million dollars not going to some other Tzedkah that might also be worth and have a much greater success rate.
Would you be in favor of IVF treatments if the money went in to instead of Tomche Shabbos. Or what if a Yeshiva was forced to kicked out a kid because the parents couldnt pay and the yeshiva couldnt afford to keep him.
In a world of unlimmited funds this would be a great thing, but this is not the case