One thing to consider is that ALL Christian denominations considered contraception immoral until the Anglicans changed their position at the 1930 Lambeth Conference (Resolution 15).
Please note the words from the 1920 Lambeth Conference:
We utter an emphatic warning against the use of unnatural means for the avoidance of conception, together with the grave dangers - physical, moral and religious - thereby incurred, and against the evils with which the extension of such use threatens the race. In opposition to the teaching which, under the name of science and religion, encourages married people in the deliberate cultivation of sexual union as an end in itself, we steadfastly uphold what must always be regarded as the governing considerations of Christian marriage.
Contrast that with the words of the 1930 Lambeth Conference:
Where there is clearly felt moral obligation to limit or avoid parenthood, the method must be decided on Christian principles. The primary and obvious method is complete abstinence from intercourse (as far as may be necessary) in a life of discipline and self-control lived in the power of the Holy Spirit. Nevertheless in those cases where there is such a clearly felt moral obligation to limit or avoid parenthood, and where there is a morally sound reason for avoiding complete abstinence, the Conference agrees that other methods may be used, provided that this is done in the light of the same Christian principles.
Take a look then at the Lambeth Conference of 1958:
The Conference believes that the responsibility for deciding upon the number and frequency of children has been laid by God upon the consciences of parents everywhere; that this planning, in such ways as are mutually acceptable to husband and wife in Christian conscience, is a right and important factor in Christian family life and should be the result of positive choice before God. Such responsible parenthood, built on obedience to all the duties of marriage, requires a wise stewardship of the resources and abilities of the family as well as a thoughtful consideration of the varying population needs and problems of society and the claims of future generations.
So maybe the question shouldn't be, Does the Catholic church consider artificial contraception akin to abortion or is this more of a 'don't eat meat on Friday' sort of rule?, maybe it should be more along the lines of "Why did the Protestant churches change their tune? Why, if something was immoral in 1920, did it become the responsible thing to do in 1958?
(Please note, I cited the Anglican church as an example. The other denominations had, to my knowledge, a similar pro(?)gression)
Eating meat on Friday is not a grave sin. Contraception is. Yoy go to hell if you don't repent and stop contraception. You will not go to hell for eating meat on Friday. Eating meat on Friday is a Church Law. Contraception is God's Law.
The majority of Christians are Catholics. In addition, the Orthodox Church was until very recently universally opposed to contraception, and a number of Protestant Churches are also. So most Christians in theory hold to a religion that considers contraception immoral.
Does the Catholic church consider artificial contraception akin to abortion or is this more of a 'don't eat meat on Friday' sort of rule?
Onan was killed by God for practicing contraception (Genesis 38), the New Testament condemns pharmakeia (Galatians 5, Revelation 21 and 22), and common sense tells us the natural end of intercourse is attempted pregnancy, so it is considered a natural law to not purposefully block insemination and fertilization.
Not eating meat on Friday is an Apostolic Tradition - the Apostles instituted a weekly fast on Wednesdays and Fridays that included abstaining from meat - see the Didache. This was to differentiate Christians from the Jews, who fasted on Monday and Thursday.
While no expert on this topic, I think most christian churches were against contraption till fairly recently. By recently I mean 1930.