It's almost like trying to squish different security architectures on top of each other doesn't work well. It's a nice idea, but it was either not going to work smoothly or be a big security issue.
On Linux it's a CLI privilege escalation program, having a GUI pop up when you can just take user input from the terminal the user is already using is kinda...
There's a reason why pkexec is a separate thing from sudo on Linux. Two separate programs that handle two separate tasks. Sudo is intended for CLI. pkexec is intended for GUI applications and is provided by the Polkit framework. It's that pointless work flow slow down you hate to see.
So if I'm understanding correctly they now let you type a command to open a new window to check your credentials (like polkit?) instead of asking for it in the tty? And the only new thing is that you can elevate your privileges in an existing tty (before you would need to start a separate admin terminal right?)