The point of the difficulty bomb isn't to put a deadline on the developers, it's to prevent a situation where node operators get complacent and stop updating their nodes.

It forces node operators to come to consensus on whether to fork alongside the developers or to fork in a different direction. It removes the option of doing nothing and letting the Ethereum chain stagnate.

For the same reason congress keeps passing appropriation bills without fixing the problem that makes them keep on having to pass appropriation bills.