If you want to support abortion but oppose this, then you need to say that a fetus is alive -- is a person with some rights -- but that those rights are superseded by a woman's absolute bodily autonomy. This would be a stronger position: Rather than saying that fetuses aren't alive, you'd be saying that women have a right to kill in certain circumstances.
We don't even need mechanical wombs to bring these clones to term. A woman could gestate her own braindead clone to provide organs for herself later in life, or a man could work with a female partner or paid surrogate. The only missing technology is that needed to allow the braindead body to develop from a baby into an adult. We already have life support technologies that seem applicable, but they've never been applied in this way. Possibly certain hormone injections would also be needed, to transition through puberty.
This is all so logically clear, and the stakes so high -- immortality? -- that I'm a little surprised nobody has been ruthless enough to attempt it yet.
There used to be Forbidden Cities with water-clocks to track the ovulation of concubines. The ancients could ruthlessly apply logic. Moderns seem not to. I guess it's about avoiding retaliation.