Actually - something like 20% of the first class males survived. (And some also in second and third class.) This was below the % of women who survived ( aprox 30% for third class, and higher for first class). Nor did all the surviving men do anything sneaky or pushy. Mostly survival depended on the side of the boat and the location at the time of the crash ( which in turn influenced the chances of reaching a launch-able lifeboat). Some boats launched 'not full' just because where the boat was... passengers couldn't reach in time. Or because the ship was tilting such that it was too dangerous to wait. Some passengers waited too long to report to the boats, thinking that a wreck was impossible.
(This is not to stay there were not other, less pleasant, factors to consider. Just that Jeeves wouldn't have to deck Bertie in drag. It would be sufficient for him to have memorized the lifeboat locations and be very firm about getting Bertie out of evening clothes and into a life jacket - and a life boat - STAT.)