Not simplified much. By the silly rules in the US, during the transfer you must go thru immigration and even get your bags and check them in again.
Yes there’s pre clearance in Canada. This would ease the border a bit. But there’s still a risk that something somewhere will go wrong.
The main reason I stoped routing thru the US 10 years ago wasn’t ICE. I didn’t like the way border agents were rude and disrespectful. I felt like I was being interrogated every time and didn’t feel welcomed there. So I decided to vote with my wallet and simply not fly thru.