Thanks for your answer. I was told by some developers that in big projects they usually have one singleton, two at most. With this minimalist we can easily end up with 40, 50 or even more Singletons which sounded like a no-go to them. I can't tell myself, I don't have enough experience.

I mean their explanation makes sense. Basically you want the least possible global variables (not to overload the memory/CPU), and with the Minimalist approach you end up having lots of unnecessary global variables — albeit necessary for the architecture purposes. I guess there is a consensus here. The question I have, is it really that important? Does it really have that much of an impact on memory/performance. Maybe it doesn't in small apps but does in big apps. So then, when does it start to be a problem?