My understanding is that the Great Tribulation is not just the seven years of the Roman Judea war,
AD67-73, but the consequent punishment also.
The Old Covenant is actually several covenants; there is a Levitical Covenant, the covenant at Sinai, and the Covenant added at Moab. [ And for covenant experts, I suppose there are also a Davidic Covenant, and one with Noah as well]
Anyhow, within the covenants, there are punishments, curses, for disobedience. The Jews didn't just have their country
overrun and torched by their colonial masters, they were then sent into a very long period of diaspora.
Over the last two thousand years, the Jews have suffered a lot of persecution, and this I personally understand as
all being part and parcel of the Mega Thlipsis - the great suffering.