I find it kind of contradictory that in the article you say that you shouldn’t mount because you…
Christos Dimitroulas

There is another article about it — https://dev.to/thekashey/infinite-war-995

In short — there is a different “depth” of shallow and mount testing. While shallow is a good way to assert a “skeleton”, you might prefer to use mount, but it might cause “infinite” amount of components tested, instead of a predicted, scoped and needed.