It was a strafing blow against the notion that something is 100% good, or 100% bad for the society, and that even the current best arbiter is far from ideal, for very important reasons that need to be understood. (as failure to understand those reasons, is often causal in why people hold such idealized notions, and are so willing to go "full crusader")
In respect to the original concept discussed-- abortion-- the termination of pregnancies is a very "subjective", and "emotional" item at its very outset. You cannot just blanket away the way people feel about things, or worse, wholesale discount other people's views, when ones own views are equally subjective. (that is to say, the assertion that abortion is "baby murder!" is just as flimisly based as the assertion that "Abortion is perfectly OK, and everyone should be able to get one for any reason, any time."
Roe vs Wade is such a controversial hotbed because it gave legal weight to one side over the other-- EG, it allowed one side to 'WIN!', by imposing a nationally enforced position.
since the only real truthful things about abortion are that it terminates pregnancies (duh), and that it does so with surgical implements that can cause permanent uterine scarring, and even when there is full familial and societal support, it frequently causes emotional upheavals in the woman who gets it (because of radical and sudden changes in hormones, if nothing else)--- we can pretty much draw a conclusion that it is at once "ultimately effective", but should be a last resort type thing, not the go-to solution, or at least that's my take-away.
When the goal of legislation is to be the result of representative democracy, -- it kinda makes sense for laws to be representative of their demographic populations.
The population of the US is deeply divided ideologically on this issue. Hence the need for isolated and varied legislation, instead of "CHOKE ON IT, ASSHOLES!" type legislation. That latter is what dictators do.