And root canals can be fixed, and re-fixed, and re-re-fixed multiple times if things happen to go wrong. None of the alternatives we have so far come close to a natural tooth, even if it's just a crowned dead root stump.

The reason implants suck is that they don't have a peridontal ligament, instead they're rigidly attached to the bone. This means all kinds of issues like bone resorption due to non-absorbed shocks, lack of an natural immune barrier, poor proprioception.