The problem with 3rd class passenger not getting to the lifeboats was that the boat deck was accessible to I class, II class and ships crew. The III class folks were completely unfamiliar with that part of the ship (and parts leading to boat deck - the whole superstructure). At first some officers were mentioned to have enforced class segregation between areas but that was also a time when people went back to their cabins because "this ship is unsinkable, nothing bad will happen".
When it became clear the ship is doomed the III class did reach the boat deck but already most life boats were launched.
This is almost certainly because of the social media trend to destroy public bathrooms. Not "teehee I pulled out a lot of toilet paper" but "I body slammed the air dryer until it broke off."