I mean the metric itself. It doesn't tell you anything other than I'm a Steam user and my client is logged in. I'm not active an user but I have an active client. If I was engaging with the client, browsing my library, using the community functions or the store I'd get it.
I don't know what the consoles do. I know Microsoft report GamePass and [previously] live subscribers, and Sony report PS+ subscriptions. If either are reporting active users where I'm not using the console, that's also unhelpful. Anything else is overselling the actual activity of users.