Greetings Jurgis --

I'd say the answer to only-C compsci in school, or only-Java,
was the phenomenon of Code Schools, with their Bootcamps.
One discovered the short cut into industry was not a compsci
degree, but a crash course in exactly what you're saying: a 
combo of py and js.

As you know es6 is looking a lot like Python. I'm coming to 
js through React world wherein a recent revolution got all
the developers turning their classes, a new thing, transpiled
by Babel, into functions only.  You could do that now, and 
yet preserve precious state in your Component objects. Yes,
I know, that's all JS echo chamber, as seen from the outside 
by a classical Python player.  The two worlds combine through
Redux and Django, right?  Learn all that in Code School, forget
college, and land a job.  Leave compsci to the ones wanting 
to support whole new languages and so on. It's a big world 
with room for many career tracks.

Because JS world has been such a moving target, and because
textbook companies publishing to wood pulp (paper) especially
fear obsolescence, tying the curriculum to a "for the ages" language
has been a pretty good strategy. C isn't going anywhere, C++ 
either, and they both take you deep into the guts of the machine,
thinking low level bits and bytes, and what better time than when 
you're still young in high school and wide open to all this new 
information.  Presumably you have time to concentrate and access
the equipment (not a given in many childhoods I realize, with many
fighting for that privilege through adulthood).  

I'm not dissing the high school approach therefore, and think the 
Code School alternative has been, for many, a good compromise, 
as in "no need for more college, time to jump into industry".  PY 
has proved more anchoring than JS in that it hasn't morphed so 
radically over the years.  Academia has put a lot of weight on it 
and it has borne the weight well.  JS inspires functions as objects
(passable as arguments) as much as PY does.

The door I've left open is for colleges and/or high schools to 
offer more tracks, a greater variety.  Python has made huge 
inroads as everyone's "first language" in the curricula around 
here (less so JS, because of the reasons I mentioned -- morphing
so fast).  One needn't abandon the C/C++ track as if it's now 
obsolete.  We're just not accustomed to offering so many branch
points in early education.  There's a bias around here towards 
college vs. not college bound.  Anyway, long discussion and 
much that parallels what you're thinking, I'm thinking.

Kirby in Portland, Oregon