Unfortunately reflection is so widely used in .Net libraries and core frameworks that code removal during linking becomes more or a less impossible without spending A LONG TIME decorating an xml file with code removal exceptions. I have done it on Xamarin iOS, it is not fun. So one of the prime dreams of having .net AOT of having an easy way to create a COMPACT self contained native exectuable dies when it hits real code.
Source generators may solve that going forward, but that is going to take years to filter out to nuget library land.
There are other advantages of AOT, sure, but I think R2R that is in .Net already covers a lot of those.
They need to solve the poor linkability of .Net code first IMO. I think Microsoft realise that, especially if they want Blazor client side to work.