98% of the people that initially thought (Python for Threads - OMG performance!) work at a company that will tell you straight up they expect 100M RPS in a year or two, will actually only get to 50k RPS in 5 years before the "Our incredible journey" letter is issued.
I use an unscientific rule of thumb that 10-100x scaling is about the most to plan for except for exceptional cases. Anything beyond that ends up with overcomplicated bloat for a "tomorrow" problem.
Being able to handle spikes and iterate quickly is probably more important.
