Very interesting post.
My bachelor's thesis was a expert system for stock trading
implemented with Borland C++ 1.0, and D would have been a good
fit as well if had been an option in 1989, so I understand why
you think that financial development will make D popular.
But that's the exact opposite of what trending languages do at
the moment (Go, Kotlin, etc).
They care to solve the basic problems of the casual developer :
implementing desktop, mobile or web applications.
Not the most interesting jobs maybe, but that's what pays the
bill of many of us, the "less skilled" developers who are not