I use C# at work, the syntax is better than Java but there's one huge issue: good luck getting it to work without Windows and Visual Studio.

.NET core is still very immature, we had to back out every time we tried to use it in production. Maybe in a few years it will be good.

Java on the other hand has support for many IDE's, package managers, web servers, JVM's, OS's. You can swap out pretty much everything, no vendor lock in issues at all. The open source community is far stronger as well. So many times I wanted to use a cool database and found out there's no official C# client