[wbkang]

> I'm trying to get my head around how I would know something is the old school way that should be replaced with an idiomatic Modern C++ equivalent without knowing what the old school thing is in the first place.

I'd recommend ISO C++ FAQ (https://isocpp.org/faq) as a starting point.

I think it's important to know the new, recommended way for each of the old, worse way. Multiple ways to do things is an integral part of learning C++ - even going back to the original release (new vs. malloc, etc) ;)