That's true but if Java had been designed with a "synchronizable" keyword applied to classes, I wouldn't consider that a radically different language. The prevalence of unnecessarily lockable things is unfortunate from a JVM implementors perspective, slightly convenient from a user's perspective, but ultimately not a defining feature of the language or platform even if it may have seemed important in 1995.

When I think about Java concurrency today I tend to think of java.util.concurrent or the JMM. Perhaps that's odd.