In the EU, and probably elsewhere, there are entire engineering shops of which the one and only purpose is to reverse engineer competitors’ features and figure out a legal way to get around patents and replicate those features.

No interoperability there.

Some people I know do that for a living in the auto industry.

There is some variation within the EU, with different national laws. In French law at least you’re right: reverse engineering is allowed only for interoperability and you’re not allowed to distribute decompiled code.