Most prophecy in Revelation deals with the Jewish people.
Revelation speaks much of 7 (Christian) churches that are made up of Jewish and Gentile "Believers". When it speaks of Israel it distinguishing between Israel Believers and non-Believers. The reference to the 144,000 is in reference to Jewish Believers. I.e., "Then I looked and saw the Lamb standing on Mount Zion, and with Him 144,000 who had His (Christ's) name and His Father’s name written on their foreheads." - Rev 14:1
Much discussion about Israel's position and role is conflated IMHO. Israel (in-Christ) must be distinguished/separated from Israel (rejecting-Christ).
The prophecy in the book of Revelation is for the Jesus followers - whether of Jewish or gentile heritage.
Chapter 2 and 3 are to churches that are varied from mixed to mostly gentile.
Chapters 5 to 20 are about the fall of Jerusalem in 70 AD - and we read about not only the 144K Judeans but also the vast multitudes from all nations who are included in the worship of the Lord.
By the time John wrote the book of Revelation *around 65 AD*, “Christianity” was still a sect of 2nd temple judaism.
Current day Judaism is derived from Phariseeism and actually dates to AFTER 70 AD, so is a “niece” religion to Christianity and about 40 odd years YOUNGER