Still not quite sure what the different design ideas behind Xamarin and Maui is

Xamarin had separate projects for each platform, whereas they're all together in MAUI. Also Xamarin was tied to .NET Standard 2.1, whereas MAUI uses the latest .NET releases (starting with 5 or 6 - I'm now on 8). MAUI major releases now come out at the same time as Visual Studio updates. Also, as mentioned, MAUI uses handlers, but I'm still trying to work out how you actually use one to create a property (sigh). There was a few, annoying, breaking changes too. e.g. in Xamarin I could define the span and height of an element in a Grid with a single command, but now I have to use two (for some bizarre reason setting the column span is now entirely separate. I ended up writing my own function so I could do it all in 1 line again).