>When I studied it, the "&&" syntax and type deduction rules seem to be "irreducible complexity".
That may well be, given a particular set of constraints. But that is exactly the issue with C++ today. It's a conglomerate of powerful and diverse features, and so everything that gets added interacts in countless ways with everything that's already there. There's no orthogonality at all. Everything is both irreducibly and impossibly complex at the same time.
You're right that meta programming is inherently more complex than other issues. But it's not the only area where C++'s complexity is outgrowing our (or at least my) cognitive capacity if the goal is to write reasonably reliable code in a reasonably productive way.
That may well be, given a particular set of constraints. But that is exactly the issue with C++ today. It's a conglomerate of powerful and diverse features, and so everything that gets added interacts in countless ways with everything that's already there. There's no orthogonality at all. Everything is both irreducibly and impossibly complex at the same time.
You're right that meta programming is inherently more complex than other issues. But it's not the only area where C++'s complexity is outgrowing our (or at least my) cognitive capacity if the goal is to write reasonably reliable code in a reasonably productive way.