I hope not and no physical copies delivered before release date. No matter what drm or encryption is used, if the product is delivered anywhere before release it will be pirated before release.
Steam will not crash due to EU4. Its not like this is Sims 5 or Farmville 3.
The game will be pirated regardless, I don't really see the problem. That said, if you pirate this game, and I notice, you'll be strapped on a Galleon for a one-way trip to Australia (Sorry australians, nothing personal)