In theory yes, the algorithm could be changed or even moved away from proof of work and towards proof of stake (I think ETH is doing this?)
In practice bitcoin is somewhat resistant to large changes or forks, most anyone who would consider any type of alteration to the existing implementation forked off with bitcoin cash for a relatively minor change (block size). That self selection has left a staunchly "traditionalist" majority in the remaining bitcoin community.
In practice bitcoin is somewhat resistant to large changes or forks, most anyone who would consider any type of alteration to the existing implementation forked off with bitcoin cash for a relatively minor change (block size). That self selection has left a staunchly "traditionalist" majority in the remaining bitcoin community.