"Being just the start, MSI packages may very well be supported for at least a few more years on Windows 10. However, by looking on the GitHub repo of MSIX, there are some hints that Microsoft envisions a future where MSIX not only replaces the MSI but also creates a package format which cross-platform Microsoft applications can recognize and use on any platform (iOS, Android, MacOS, and Linux)."
https://www.advancedinstaller.com/msix-windows-package.html