I'm guessing you only read the issue or title on that link, because the second comment on that issue is from one of the Gradle maintainers suggesting using toolchains (which I linked to), with follow ups from various users advising some success, allowing them to target Java 16 while running Gradle on an earlier, supported version.

The last comment by a gradle team member, before closing the ticket says "... you won't be able to run Gradle 6.8.x on Java 16". Some users having some success compiling isn't really a ringing endorsement of a build system when it's clearly not working completely.

> "... you won't be able to run Gradle 6.8.x on Java 16"

Exactly. But you could run Gradle on Java 8-15 and use the new toolchains support to build with Java 16.

I'm not saying setting up toolchains is frictionless or even reliable yet (given the feature is so new) but it's there.