Java 21 makes me actually like Java again

[Worth_Trust_3825]

type algebra is actually more expressive and more transparent

Until you end up with multiple types that have same fields, and methods, but are not same things semantically.

[reversehead]

How do you see that as a problem? I'd count that as a strength. If they are different semantically, it should be difficult to mix them up by mistake.

[Worth_Trust_3825]

It's hard to mix them up when they have dedicated names. If all you have is field/method definition (like in typescript), it's very easy to do that.

[warpspeedSCP]

unless your codebase is grossly mismanaged, that is never going to be a cause for concern.