Yes, in fact GPUs are perfect for this. Here is a Monte Carlo financial simulation I built in WebGL 2. https://james.darpinian.com/money/ (Warning, programmer UI) It performs one million Monte Carlo runs instantly every time you move a slider. Each run is one execution of a pixel shader and they all happen in parallel.

WebGPU will make this kind of thing more accessible. It's kind of a pain to do it in WebGL, but even so it's still totally possible and worthwhile because you can easily get 20 times the performance in many cases and handily beat native CPU code even on the web.