• Integrated automatic uninstall (which is fast).
• Automatic online updates.
• Apps have their registry and AppData writes redirected to a private location, which Windows can then clean up. It's a bit like the macOS app sandbox but the app isn't actually sandboxed, it's much lighter than that and there only for clean uninstalls.
• No need to retain downloaded packages or installers.
• If you use the .appinstaller feature, only the parts of the package that the user doesn't already have are downloaded so apps that use big runtimes (electron, jvm, flutter etc) can turn into small downloads if the user already has such an app.
• Don't need admin rights to install.
• Integration with Windows network admin tools. MSIX is declarative so Windows can do things like make apps appear without them being actually installed.
• There's a tool that monitors other installers and converts them into MSIX files.
So Windows has solutions for a lot of these problems. Unfortunately developers don't know about it and that's partly because Windows has a lot of bugs, especially in Windows 10 (which hasn't been receiving bug backports for a long time now). The best way to get these features is to use Conveyor which is a tool that abstracts you from the packaging tech and automatically works around the bugs (Disclosure: I wrote Conveyor). It also extends it with other useful features like checking for and automatically applying updates every time the app is run (if you want that):
MSIX indeed picks the install path for you but very few users want to change it these days. Chrome installer doesn't let you pick either.
Having a better alternative while still not fixing the old system does not shield the OS from this.
Neither does the existence of other bad apps like Chrome shield the new system from the blame for making the same obvious mistake, especially when the example of macOS with its simple bundled app folders that you can just drag&drop around has been right there the whole time
Something inbetween the two is worse, you get installers and uninstallers that are half-broken because they can never assume stuff about your system and just be broken but you never know exactly what they're doing.
Windows and macOS are both inbetween to various degrees, but I think macOS is a bit closer to Unix style (excluding App Store apps).