To add to you, I present my mere anecdote:
I have an uncle who, somehow, manages to get all kinds of adware and whatnot on his computer no matter what antivirus/internet security/voltron PC protection suit. Then comes me periodically cleaning up all that, often backup his stuff and refresh the installation. Eventually I convinced him to let me install Ubuntu, since he needs a browser and whatever PDF reader.
Yes, now he doesn't have those malwares anymore, but my recurrent task has become running "apt-get autoremove; apt-get autoclean".
If Linux wants to target "desktop", then those trouble should be transparent to the users.
As a long-time Linux user, I can appreciate that anecdote.
I've a few home servers that are pretty stock Ubuntu with most of the default partitioning / settings, because nowadays I 'just want stuff to work' rather than spend hours tweaking & optimising. After a few rounds of apt-get update & apt-get upgrade, the update process broke (with pages & pages of error messages), because /boot got full of all the myriad kernel point releases that had collected there and Ubuntu just left them hanging around.
apt-get autoremove clears away all this old gunk and will let the update process work again. But a 'simple' (I don't mean that in a bad way) desktop user will not know what the problem is and will not be able to make sense of any of the errors. Even if they spot a 'disk full' somewhere in the output (do they even see the output with a GUI-based update?), it won't help. "Disk full? But it shows I've got gigabytes of space here in my documents folder?"
It's these and all the other 'thousand paper cuts' that are still blocking every day desktop Linux use.
I encounter this same thing periodically myself. I found out how to fix this, but a "normal" user will never, ever manage to get around this issue by themselves.
Most of the time it seems that desktop Linux would be completely ready for mainstream, but then you encounter something like this and remember why you don't recommend Linux for your non-technical friends and relatives.
Sure I cron, but only if I knew it'll be a common occurrence. The first time he faced it, I was in town, so I just dropped by, did it, and thought it's an anomaly. The other times I was in another city, so I walked him through the process over the phone. I'm not going to walk a layman through the process of adding a cron job over the phone.
Besides, you're missing the point. That should not be something a layman user should encounter in a "wannabe" desktop OS.
Indeed - how does Win 10 do on eliminating cruft, like old update files and such now, MS Windows used to be terrible at it but I've barely any experience of Win 10 beyond installs and some basic troubleshooting.
I regular user would use something like Muon software center which manages it all and pops up update prompts when necessary in a similar way to Google's Play store on Android.
> how does Win 10 do on eliminating cruft, like old update files
I cannot answer this, just speculating: Windows does not create multiple partitions by default, so as long as C:/ has free space left, it can pile on without a care in the world. And by the time that it actually fills up, the average consumer would go buy a new PC anyway (or pay someone to cleanup the mess).
Yes, this is largely how things have worked in the past. They had "disk cleanup" (as far back as XP at least) that removes some install files and such. Programs like CCleaner work to remove that kind of excess - but I was specifically asking what Win10 was doing as a comparison to the complaint that Linux distros don't [apparently] handle removal of [some] install cruft without intervention.