That won't stop people from expecting it and emailing you about it.

So create a filter that deletes and/or autoresponds to all inquiries to the project's support e-mail address.

"Bad support" is when you promise some (explicitly or implicitly), but fail to provide.

It's not "bad support", it's "no support". The same state it is now already.

Nobody would complain about lack of support if you specifically state that there won't be any. After all, it's the dump of source code and blueprints, not some end-user products you see in a store.