No, the Tal Shiar are still murdering psychopaths, even by Romulan standards. Because, y'know, the majority of the Romulan people are absolutely terrified of them, one way or another.
And the "History shows that races of people do not change even with time and circumstance" line is complete BS. If you were an actual study of history, you'd know that.
Actually, I AM a student of history and am 62 years old as well.. I'll contest your assertion then..
Look at the middle east.. Theyve been at each others throats since before buddha walked the earth.. They still are.. No change.. Look at China.. When Emporer Qin united the nations we now call china he began a centuries long mistreatment of his people to build his wall, which other emporers followed up on and continued till Ghengis Khan became emporer.. Today, hundred and thousands of coal miners die every year doing underpayed back breaking work in their mines.. Again, no change..
When the people that became america first came to this continent they were the rejects of the world. no one wanted them and most hated them.. I give you todays social climate in where everyone still pretty much hates us.. again no change..
races do not change.. and niether would the romulans..