Earlier quoted context omitted.
You ... are not ... Instagram. Okay. Get over it. Python is fine. Threads are fine. Go is fine. Clojure is fine. Java is fine. PHP is ... okay I won't go that far. :) You fix the problem when the cost required to fix the problem is finally less than the opportunity cost of fixing something else.
I would prefer not to deal with "scaling up" for workloads that could run in a single process on commodity hardware. I've mainly worked at companies that would be bankrupt if they used Python the way Instagram does.
You need a market. You need paying customers. You need cashflow. You need features. You need a business plan.
You don't need scaling. Ever. To first, second and third order approximations.
Your company has a higher probability of bankruptcy than needing scaling.