>How many practical, modern use cases does Cpp have at this point for those of us who don't work in a few very specific verticals like finance or game dev?
I understand your reservations but keep in mind that the blog post is intended for an audience that has already bought into C++ programming and therefore, may want to improve their baseline C++ skills.
It's not an an evangelism article to convince those not using C++ right now.
That said, to answer your question directly... I think that programmers who require high-performance code with low-to-zero cost abstractions will self-select into C or C++ ecosystems. In other words, a programmer thinking about writing a web app to track food recipes isn't going to be perplexed about choosing "C++? vs Ruby? vs COBOL?". Like you hinted at, the domain of the app constrains what the programming languages will be realistically chosen.