I'll grant that it's a bit of a pedantic response, though I do genuinely think that it's better not to misuse terms. It also affects what you appear to be calling for as a response -- just because Apple-and-Google are the two major players in a market doesn't mean that antitrust/monopoly laws are the right things to use.

Re: Google, given that you're privately distributing software to a private organization, couldn't you just sideload it onto the Android devices in question? It seems reasonable enough to for them to want you to have a developer account if you're using their infrastructure to distribute these things. But my (minimally informed) understanding is that, unlike Apple, Google doesn't force you to have a signing certificate from them or anything for the software to even run on a device.