Dism.exe /Online /Cleanup-Image /AnalyzeComponentStore
That is not available to Win 7 or 8, only 8.1, but of course you know that.
There was a feature built into 8 that was supposed to cut down the space consumed by WinSxS, but that only ran once a month, and was not particularly effective, from what I've read. MS introduced those tools as a response to growing concerns around the very real problem of the amount of space that WinSxS was taking up, both in Win 7 and 2008 R2.
So I agree that any installation of Win 7 that grows to a very large size is indicative of a problem, but not in the sense you mean.
The problem is that Windows with its "component store" model basically keeps a copy of every version of every dll, exe etc. since the original installation, in case it is required by an application or to roll back a patch or update, and there's very little you can do about it. You can run Windows Cleanup (in admin mode) to look for superseded updates and look for orphaned updates, but these will barely put a dent in the problem. And the problem is purely down to MS's implementation. The OS runs just fine, but it is going to grow, inexorably, over time.
Bear in mind also that these Windows repositories also contain components from other MS applications (mainly Office) and 3rd party applications, so the more applications you have, the bigger the problem will become.
I'm talking here about Win 7 - I know that the OP asked about Win 10 - and this also applies to Win 8, and the equivalent Server OSs also. But this is, IMHO (based on almost 25 years of working with MS products), unlikely to become less of a problem as we go forward. MS have always been profligate with other people's resources, and what I've seen of 10, and the efforts to push it out, do nothing to make me change my mind. I would be pleasantly surprised to be wrong, but I'm not holding my breath.
I would happily place a significant wager that the average Win 10 installation from 2016 that is updated regularly will be at least 40GB in size in 5 years time, assuming it has not been re-installed in the interval.
SD