I think those that choose to go into programming purely because it can earn well (I have nothing against this by the way) will choose to invest in one of the more popular languages because there are more job opportunities in it. Also there would be any, let's say, Common Lisp bootcamps so it is more likely that the people that know it have picked it up because of some passion.

When focusing on nice languages it is very easy to get hired for positions that need it because there is less competition. Though, contrary to what I would have expected usually it pays a little bit less. The highest paying jobs I had so far were in Java.