They shouldn't have been lazy and just emulated. Super Mario 64 has a native unofficial port thanks to the source code leak that runs 1080p60fps 16:9 with updated camera controls. If people can do it in their spare time Nintendo should absolutley have done it. Hobbyists created a superior product for free. 720p 4:3 is just a terrible port.
I agree they could've put more effort into it but the PC port isn't perfect either. Sprite based objects and characters (like King Bob-Omb, trees, coins, etc.) look very bad in the PC port while they are a lot smoother and sharper in the All-Stars version. Same goes for HUD icons and text. And having rumble on Switch is nice. I definitely would've preferred Mario 64 to run in widescreen and full HD, don't get me wrong. Just pointing out that there are certain things the All-Stars version has going for it over the PC port. Although there could be a newer version of the PC release where these things are fixed.