An excellent suggestion Paul. COBOL devs are the highest paid in the industry. Since the language has now developed to become object-orientated they no longer need to lie at parties about what they do for a living.
FORTRAN is one of the two main languages for high-performance computing and an important part of an Engineer's skill set. When we get new graduates in at work we typically have to teach them the language.
And as for BASIC ... can someone help me out here?
On a more serious note I agree with your reservations on vendor lock-in. This is why I would not support Delphi, no matter what the advantages or the disadvantages of the language are.
The furthest I've gotten with an interest into COBOL is acquiring (I think for 50c) an Introduction to COBOL Programming book off a library clearance table - actually I did page through it briefly. I think COBOL is sort of the original VB 6 and in 1960 it was thought it would be dead within a decade (so the fact that it is still actually used - COBOL 2014?)
FORTRAN is also an interesting one and my jest should not be viewed as to suggest their irrelevance (BASIC maybe a little, but my non-programmer take is teaching some BASIC nomenclature and cultural aspects is an important component of having in-industry humour - you'll spot the jokes on this forum) but rather the fact that the maths is too hard for me.
Although the argument in favour of FORTRAN 2015 (yep revised this year - so ...) as an introductory language is probably more in the vain of inclusion in postgraduate science studies for students who haven't done any computer science