This roughly checks out. I'm getting 66%, based on the methodology of cutting out the jug's shape from the picture and numerically integrating the filled and empty volume (e.g. if a row is d pixels wide, it contributes d^2 to the volume, either filled or empty depending on whether it's above or below the water level).
I agree that there's a lot of space between "considered disabled" and "horrible life", but OP said "suffer their whole life" which I associated with the latter.
You have no moral obligation to have children at all, even if they'll predictably have a happy life. So if their life will instead be predictably horrible (or if they will predictably ruin the lives of the people around them - plenty of severe mental disabilities seem much less horrible for the people themselves than for their caretakers), it's very reasonable to avoid it.
This post is currently top-1 when sorting by controversial. Objectively amazing bait.
The thing I said I did? Yes; here's the processed image:
If you mean the math in the post, I can't read it in this picture but it's probably just some boring body-of-rotation-related integrals, so basically the same thing as I did but breaking apart the vase's visible shape into analytically simple parts, whereas I got the shape from the image directly.