That is all valid for "is there enough lithium for Musk to make a big profit on this factory?" but is not the same for "is there enough lithium for the foreseeable future?".

There isn't enough oil to power our civilisation for the foreseeable future, but people are still building wells and selling their contents.

There might easily be enough, or it might be easily recyclable but those are perfectly sensible questions to ask that aren't answered by your thought process.