It can depend on if you want a nice interface and have windows or something or if you plan to sell it. I've been using C# and python for very similar tasks recently, and I feel its great to be clued up about both, as you can run ui's that interact and process data, and the python code can work in the back end doing the scraping or heavy lifting. I would suggest you get good at both, as they offer very good libraries, and there is plenty of code on stack for them. I think windows is here to stay, as long as it is, so is C#, and for python, well everyone loves it so it's obviously best to learn to.