0.4-preview was an early version of 0.4 that still had some cruft like the feature flag you pointed out. We removed the cruft for the release of 0.4-beta

Why don't you open source 0.4-preview too, to make your claims verifiable. The longer you take to release it (or choose not to release it at all) the more it'll look like a cover-up. If the binary is (made) public, it's going to get the AI-assisted decompilation treatment anyway.