It's annoying, but that's been pretty common for the last decade. It's just like how everyone uses "REST" to mean "JSON RPC". In the end, we all basically know what the other ones are talking about, so it's pretty pointless to get bogged down in semantics.
It's common when talking about web services, where the kind of API is generally unambiguous. The problem here is we're discussing different kinds of APIs (shell commands, MCP, REST / JSON RPC) and so calling one of those kinds of APIs "API" is very confusing.