This is a stupid comment, since whatever language you use will run into bottlenecks. What is important is how you design your architecture, is it distributed, are long running processes handled by a task manager, caching, how are you serving up your files, vids, imgs, does your db have the right indexes, is your schema optimal, geez we can go on and on. You are 100% fine running python just like Instagram, Dropbox, Yelp and many other startups did and still do. Stop distributing this FUD.
I think you are missing the point of the parent comment. He is trying to convey similar message as you are. The difference is he is not being a jerk about it.
