Sounds like they’re working on removing the 60fps hard limit that macOS has had for the past fifteen years, as part of bringing 120Hz support from the TV and tablet line to pro Macs someday.
I was thinking of the hard limit on Apple's monitors, which have always been locked at 60Hz (such as MacBook, iMac, and Pro Retina). But I'm glad to hear that macOS is ready, even if the hardware isn't! Thanks for the correction.
