I'm discussing about this/related on my local board. Here is the thing : can we expect the BTC protocol to evolve at one point to make private keys more secure ? Like making their size bigger (4096 bits instead of 256) so that instead of making a collision almost impossible, it would become totally impossible ? To fend off advances in computing.

If such advances become possible, then "lost coins" might be recoverable at some point, by people with access to supercomputers/clouds.

Would there be/should there be a grace period to transfer coins from current adresses to bigger addresses, after which older addresses would become invalid, making lost coins lost forever ?