Assad had to be brutal because the United States and Israel were funding and arming a violent sectarian revolution against him. Any state that is under that degree of outside pressure is going to deploy any means at its disposal to survive.
For much of Assad and his father's reign, Syria was a model successful nation, with excellent universities that Arab elites would aspire to send their kids to and a pharmaceuticals industry second to none. Not to mention their long standing commitment to the Palestinian cause in Lebanon and beyond.
You just omit all these facts to suit a customized, personalized grievance narrative that is completely cut off from all material and historical facts. Obama and Trump funded, directed and armed those jihadists as proxies against Assad because the Syrian government was helping Hezbollah fight Israel.
Go read A Clean Break, where Netanyahu and the Jewish neocons outline this plan for Syria. They have so little respect for Salafist/extremist Sunni intelligence that they take it for granted that they can stir them up at a moment's notice. They were apparently correct.
This is disappointing and embarrassing from David Miller.
ISIS never controlled or ruled the province of Idlib. In fact, factions in Idlib, including HTS, were in an active, bloody, and existential war against ISIS.
Miller, who is a staunch leftist, idolises Lenin, is employed by Iran, and has taken several trips there, is not an objective voice on Syria. He was once asked about the Sunnis who were oppressed, murdered, tortured, and carpet bombed by Assad and his allies.
He replied: 'They should get over it.'
This is called moral decay. It is no different to telling Palestinians the same thing.
As for Syria's history and civilisation, this was down to Syrians themselves and their golden age which occurred under the Umayyad Caliphate. Not hostile secular or sectarian tyrants.
The longer it takes for people to admit that their beloved dictators, extreme sectarian militias, or funders should have never soaked their hands with Syrian blood, the longer it will take for the region to accept them.