Servers crash even in games like WoW or Diablo3 where it's expected that colossal amount of ppl will log on at same time.
SE can't do anything whatsoever to prevent it, except early access; not everyone will pre-order, so it will reduce the amount of log-ins, by a little bit.
Players can help reduce the problems by....going to work/school/sleep/your usual stuff, and playing at your usual schedule, instead of taking days off, and staying/getting up at 4am, to spam log-in.