It's still dominant in gaming (though losing share to Unity/C#), system software, and high-performance computing (of which quantitative finance is a significant subset).

I would recommend not optimizing for number of job positions open, but for desirability of job positions. You can only have one job anyway. If you would be unhappy doing Python or Java it doesn't matter how many open positions there are, you're not going to want any of them. Concentrate on finding a niche that you can get really good at, and then figure out who's hiring for it.