"simple systems have less downtime"

That is not much of an insight. It is as insightful as saying "water is kinda wet.". Well... sure it is.

What we need to deal with, is not "make a simplest system".

Rather, we need to deal with: "build a system that does A, B, C, ... and so on". Now, if you can do all of the above and make it simple... awesome. But if you cannot do all of the above, but the system is simple.... that is useless.