Greetings in that Divine and Most Precious name of Our Lord and Savior Jesus Christ!
Its a classic circle that enters the Church and Christian in cycles based upon our Jewish roots and the Old Testament. Christians revert to Old Testament and Jewish practices to legitimize their Christianity in the context of the Old Testament.
I think the Protestants, Evangelicals, etc etc become these increasingly more Jewish Jesus Christians because they lack the structure, authority, and legitimacy of the Church as a social institution, and further they have deprived themselves of many tangible aspects of worship. When you combine this with a "sola scripture" philosophy it is entirely predictable that folks would misinterpret Christianity and delve to deeply into Jewish practices. We in the Church know the Holy Spirit is in the Church, not the Jews, so we know we can only understand the deep mysteries of the Old Testament Scriptures through the Church, not the Jews. Christians who reject the authority of the Church, naturally revert back to the original authorities, those Jews who used to debate us up and down in the Acts. It seems rather silly to me, a fad, which is accentuated by this Zionism and Israeli situation, where these Christians are accordingly brow-beaten from the pulpit to politically support Zionism, and distort the Scriptures to support Zionism, and equate Zionism with being a true Christian, and when you get twisted in this kind of confusion, it is easy to see folks look for more and more Jewish identity, because they are really becoming Jews more than Christians. That is the heart of these kinds of movements, political Zionism which reinforces and itself is enforced by religious pseudo-Christian Zionism which asserts that the Jews remain the Promised people, and that the Covenant wasn't trasnferred to the Church. It seems so sad to me that folks would rather be crypto-Jewish Evangelical Christians rather than just come back the Church, who as Paul asserts is the true "Israel of God."