I would be happy with a 15 second timer.
You're pretty much dead if you are the last one left unless you get blind lucky with finding the hatch first. Killer simply can cover more ground faster without fear of a killer finding them. Rush gens as fast as you can, because you need as many people alive as possible for endgame. That is the only answer.
How exactly did this go down? Did the Trapper close the Hatch and then somehow manage to trap both gates? Were you somehow unable to find the Hatch before the Trapper could trap both gates and close the Hatch? Did the Trapper somehow have the foresight to trap both gates well in advance?
The time required to open exit gate is 16s now, from 20s -> 16s after EGC update