I completely agree with what you're expressing here, but when you belong to an organization that claims to have a monopoly on meaning and truth in the universe, a higher level of consistency is not an unreasonable expectation.
Catholics and Pentecostals are different organizations. Back in the old days we used to purge non-orthodox views, but that's not as tenable anymore, so we have thousands of interpretations. In any event, the traditional Christian view is that circumcision is no longer necessary, as stated by Paul several times in the New Testament.
There is no such thing as 'the traditional christian view.' There are many 'traditional christian views' and many times they contain mutually exclusive things. Even in the earliest records of the different churches, there are arguments and discussions about what is and isn't "christian." There sprung up groups that mostly agreed on things, and some of those tried to forcefully make others believe the same things, but they never succeeded.
The early church had many disagreements, especially over observance of Jewish law such as circumcision. But the Judaizers (as they are called) essentially lost the debate, which Paul was active in, and the Church became rather Gentile-oriented. Many other things were up for dispute as well, such as the exact nature of Jesus, but these were ultimately ironed out under ecumenical councils which ratified certain dogmatic truths such as the Trinity. Beginning with the First Council of Nicaea in 325 AD, convened by Constantine, Rome sought to define Christianity properly and began to eradicate all heretics, such as Arianism and Catharism, though some remote groups such as the Copts evaded them due to being out of their jurisdiction.
Christianity thus maintained relative internal consistency under the Roman Church, and spread throughout Europe, until around the year 1000 when the Greek Orthodox split off from the Catholics. However, they still maintain very similar dogmas (including that circumcision is unnecessary).
Martin Luther did his work in the 16th century which caused a great deal of schism in the Church; until this time Protestants did not exist. King Henry VIII abandoned Catholicism and invented Anglicanism. All of these people nonetheless still believed circumcision was not necessary and it was not generally practiced in Europe, and many of their liturgical beliefs were much more aligned with traditional Catholicism than modern evangelicals.
It wasn't until the US, with its enormous variety, lack of traditional oversight, and radical re-interpretation of the Bible by individuals, that circumcision regained some religious significance in fringe groups. Pentecostalism in particular did not start until the 19th century. However, after looking around, I can't find any evidence that even they universally see circumcision as a religious requirement for Christians. Some Christians practice it anyway, but not as a religious requirement. Incidentally, so do many atheists.
I think it can be said that not only the New Testament but almost the entire history of Christianity is against circumcision being a religious requirement. There was disagreement in the early church, and there is disagreement in some fringe groups today, but it was never a mainstream view.