Premiere actually does grade you-get-what-you-see in sRGB if your monitor is also calibrated sRGB. premiere will ignore any other color profiles. quicktime is not sRGB(0-255 gamma 2.2). quicktime(depending on the version), RGB values are 16-235 with various gamma styles like 1.8 or 2.4.
Furthermore, if you colorgrade in Premiere and your monitor is not sRGB, you will get incorrect grades because you are grading in the wrong native color profile. VLC can match premiere perfectly if you set its video output to OpenGL. Also, nvidia control panel needs to be set to 0-255 so that your gfx card doesn’t change your RGB values in media playback.
Also,
external displays are still limited by adobe’s mercury transmit protocol that is hard coded to rec. 709 so you’ll need to match that too.