Not all Chazal were Anti-Roman especially Rebbe Yehuda HaNasi and Likely Rebbi Yochanan Zakai as well
Let’s keep in mind that the period of “Chazal” covers several hundred years and several thousand miles.
Saying that Chazal were anti-Roman (or not anti-Roman) with any consistency is like trying to say that Americans are anti-British because of all the anti-British rhetoric that existed in America between 1763 and 1820 (or that they weren’t anti-British based on their alliance in World War II).
In other words, one could easily expect that they weren’t so anti-Roman before the churban (in R. Yehuda’s time) and vehemently anti-Roman after the churban. Statements of Chazal about surrounding cultures, powers and people have to be viewed through the lens of what was actually happening in those times. You can’t take statements made across the centuries by different people in vastly different places and make general statements.
The Wolf