The book of the Apocalypse--the Revelation--the unveiling of th tribulation and its consequences, written AFTER Tisha b'Av, completely negates and wipes out your false premise.
Your totally false premise and whatever you say henceforth in this thread that you have drummed up, deserves no further attention.
The Flavians didn't persecute Christians in the same empire-wide way as NeroThat didn't happen in the 90s AD :)
So Jesus said very clearly and spoke aboout the Generation that was listening to Him then
Why don't you believe Jesus' own words?