I cannot link to the article, given the link you provide, but I would say the title of the post does not equate to what the bishop said. Not nearly all abortion supporters have formally cooperated in an abortion. Therefore, "Abortion supporters are excommunicated" is an extremely misleading headline. And even for those who do formally cooperate, including the mother, there are other canons that mitigate against excommunication. Dr. Ed Peters, who on May 22 of this year was
appointed Referendarius of the Apostolic Signatura by Pope Benedict XVI (1 of only 12 in the entire world -- I'm proud to have had Dr. Peters as a professor and to have sung bass next to him in the Seminary Chorale -- I'll grovel before his vastly superior knowledge of Canon Law, but I have the better voice

), walked our class through the ways in which the mothers who procure an abortion could "escape" the penalty of
latae sententiae excommunication (although not necessarily the state of mortal sin).
In fact,
here is the bishop's entire, original article, which does not carry the headline in the post above. Nor does it say abortion supporters are excommunicated. I would say the person who wrote the headline based off of the bishop's actual statement is at best being overly zealous for the cause, or is engaging in wishful thinking, or is being sloppy in his excerpting and summarizing, or, at worst, he is deliberately violating some other commandment about being truthful.