What they are referring to is people just don't update their server because during that time they wouldn't be able to make a profit. This goes more to middle siszed businesses but happens rather often
I find this to be least acurate with debian.. on other distros a patch may or may not install a new version of that package. that can bring changes to the behavior.
On debian stable the security issues are backported. So you can patch and be sure that there is no changes to the behavior of the system. It is basically the reason all vm's i manage are debian stable.
It is also true they never crash. But that is expected of linux. It is the extreme reliabillity that is the debian killer feature for me.
That was 1st about the forced restarts (Linux always only told you that it is necessary, but let you decide when to do it) and 2nd about the commomness of it happening on Windows (restarts are necessary more often on Windows).