As co-founder and leader of http://www.openprinting.org/ I am the "printing guru" for Linux and other Posix-style operating systems. As Windows is doing now with their Protected Print Mode we are also going all-IPP-driverless with CUPS 3.x, to be fully released by the end of 2024. Mopria is one of the 4 flavors of driverless IPP printing, the others are IPP Everywhere from the Printer Working Group, Apple's AirPrint, and Wi-Fi Direct Print. All these work principally the same way: The printer advertises itself by DNS-SD (aka mDNS, Bonjour, Zeroconf) and then the client (usually the operating system's printing stack, CUPS on Linux or macOS) asks the printer via IPP (Internet Printing Protocol, from the Printer Working Group) for its capabilities (page description languages, paper sizes, trays, color/grayscale, print qualities, resolutions, ...). With this the client can display a print dialog with all available printer-specific user-settable options and convert the print jobs into a format which the printer understands (the printer is required to support at least one of PDF, Apple Raster, PWG Raster, PCLm). So most probably all driverless IPP printers will work under the Protected Print Mode, especially the wide range of AirPrint printers. So what prints from an iPhone will now not only print from Linux or macOS but also stay working under Windows.
But there is also good news for everyone with a non-driverless legacy printer. Do not through it away, it can still be used under Windows, as all printers which currently work under Linux (~10000 models) can be made working under Windows with the help of WSL (Windows Subsystem for Linux) simply follow our https://openprinting.github.io/wsl-printer-app/ on using Printer Applications (the new printer driver format for Linux).