The Church could make every serious offense or crime an excommunicable offense. But it doesn’t. Why? Because these offenses are the ones that the Church deems it necessary to point out the evilness/wrongness of the action.
Are there any politicians running on a pro-homocide platform? Are there any legislators moving to decriminalize homicide? Are there any groups out there attempting to explain the moral good of homicide? Are there any Presbyterians for Homicide groups popping up? Are our public schools teaching tha homicide is just another choice, a personal freedom that should be limited or legislated?
There is no moral confusion related to homicide. Therefore, there is no need for the Church to codify the seriousness and repulsiveness of this action in her code of law to impress upon the faithful that what they do is wrong.
There are politicians running and legislators legislating a pro-abortion position. There are churches complicit with abortion, joining groups like the Religious Coalition for Reproductive Choice. Schools teach our kids that abortion is just one among many perfectly acceptable choices a girl can make in her life for serious reasons or NO reason.
There is a LOT of moral confusion as a result. The Church chooses what it puts forward in the law as exccommunicagle-- at the time the 1983 code was written we were 10 years past Roe v Wade and in many countries abortion was still illegal but RvW broke the dam and the dominoes started to fall elsewhere. Pope JPII saw this as serious enough to put it in the code.
Maybe one day, when life is a right for all humans again, we will no longer need to convict women’s concsciences any way we can, including formal sanctions within the Church.