It would be but it is not. The difference between Java and Xojo is not only the ecosystem. It is the reliability of the language, the clean coding structure, the support, the size of the Development team, the development structure, the release system, the release cycle, the long term support System, the stability, the concistency of it’s API, the technology stack itself, the functionality, the broad community and so much more. May be you believe in Xojo. It is okay. Until you hit the borders. At that moment you leave your ability of building solutions. And yes, for many problems you can buy addond / plugins / whatever from Christian and others. But at the end: it solves not every problem you may have.
The next Part is: running on a virtual machine in case of Java is much faster than Xojo will ever be. Even after the speed boost in 2024 there is not the performance you have with Java. So you build slower Software. What ever you do.
The GUI System of Xojo is a good Idea but for X-Platform it brings also some problems. While using only native elements / components Xojo is functional reduced to the functionality all of the components in the OS have. That is nice when and if there is no need for anything else. Otherwise you need to build native GUI Software.
Looking on Java the problem is nearly the same. The GUI Components having their functionality on all platforms (Windows, Linux, MacOS, UNIX). On the other side it is so that it runs also on RiscV Systems and all known platforms. Even on RTOS I implemented with the known RTOS VM’s with success.
Writing GUI programs means: if you are still inside the conventions (FileSystem use like all times, is in Xojo the same) it works on Mac, Windows, Linux on all platforms. A jar File can be started without any modification on all platforms and it runs. Like I said: take care of FileSystem use and take care of direct Hardware adressings.
Writing mobile applications is easier. Why? While you can write Software with CodenameOne for IOS and Android with ONE Sourcecode and ONE GUI. The result is a Program where ou can generate the IOS and Android Package and on top you get also a jar file which you can run on all platforms including the GUI. But - of course - only without stuffs like accelometer.
Writing Web Spplications in enterprise ready Style is also not that complex: Vaadin is the right Choice, if you are not using their special components you can use it open source.
And here is the border between Xojo and Java. All the Stuff I was telling here is for free. Open Cource. With no upfront costs. Always with a consistent API. All with a high reliability, code consistency and functionality.
And you can decide: do you want to write your Software with an exoensive tool, many bugs, no real consistency or with a language and n ecosystem behind which is in broad use? Your decision. For me it was and is simple.