The primary performance benefits with Enterprise are access to the G1 garbage collector and profile-guided optimization
Profile guided optimisation for native executibles sounds cool. Too bad Oracle wants to keep it closed for monetisation.
ART also does PGO for free, as does OpenJ9. Both of which also handle reflection.
The thing with Java ecosystem is choice of implementations, instead of Microsoft's single implementation, specially now since most of Xamarin's work has been consumed into modern .NET.
With that said, trimming, also known as tree-shaking, which is required to not have massive binary size, has to know at compile-time which types, members and metadata tokens are reachable. This means that certain patterns of unbound reflection are by definition not statically analyzable and require the user to annotate (with [RequiresUnreferencedCode(params)]) the corresponding types with details of what they need the trimmer/linker to preserve (the entire assembly can also be rooted but, well, that's bad for size).
Other features like compiled expressions have received proper interpreter fallback which makes them just work(tm) without developer intervention.
You can also see that GraalVM Native Image is subject to very similar restrictions[1].
[0] Like pre-generating generic types/method bodies for Unity with special tooling. NativeAOT currently has (planned to be deprecated) rd.xml to manually instantiate certain generic methods and root specific types, replace their bodies, etc., it will probably be fully superseded by further expansion of attributes-style annotations API or obsoleted by improving compile-time analysis in the future.
[1] https://www.graalvm.org/22.1/reference-manual/native-image/L...
p.s.: quick search shows that Java Swing is plagued by similar issues with Native Image (not mentioning having to generate metadata annotations) to making .NET's GUI frameworks work with NativeAOT save for certain blessed templates/workloads introduced in .NET 8. Java AWT appears to be faring somewhat better on hello world examples but I suspect it experience the same fate as the templates for WinForms that the community has come up with so far (let me know if that's not the case).
In ART's case that metadata is even shared across devices via PlayStore, which gathers and uploads it, packaging it for download along the APK for new installations. This metada is dynamic, as more devices take party into executing newer code paths.
This is the beauty of Java ecosystem versus .NET, the plethora of implementations, with different approaches solving the same set of problems, allowing us in many cases to pick and choose.
From Real Time GC with AOT compilation used by US and French military in embedded systems, factory automation robots, phones, infotainment systems, M2M gateways, runtime snapshots between executions, or crazy ideas like having PGO data from cloud based JITs sharing executable code.
(please, please read the documentation first before making confident assertions, like in this case, and at least google discussed topics to actualize the knowledge on the points in favour of which you're arguing)