IMO, the only reason you would say that is that you either know nothing about Mathematica, or that your knowledge of it is very superficial (speaking as someone who uses it daily).
I actually used it for about 3 years (2009-2012) for stochastic modelling (insurance). We moved off the platform because to be honest we rewrote most of the functionality we used in C# over a couple of weekends.
When I make those comments, they are about the language, not the ecosystem or the product as a whole.
The language is merely ok.
The ecosystem, particularly with the amount of data feeds you can plug into it is pretty good as is the sheer enormity of the library of off-the-shelf functions it gives you.
Ok, your comment was not about what I thought it was (if I understand your response). It was really about how fast Mathematica is and not about the symbolic functional / lisp like / whatever of the language?
It's more about what people use it for and how they use it rather than capabilities. I was a little cranky and sarcastic initially and I don't think that came across clearly!
Sorry there was a little intentional derision in that comment.
My gripe is more that for the multitude of problem domains that you can represent in mathematica, a huge amount can be done off the shelf for the same effort with something a lot cheaper if not entirely free. Very few people need or use the capabilities past the very basics.
