Good point about the ephemeral nature of trying to fix actual problems (in reality, or in attitude) by futzing with words!

The moron -> retard -> special -> different -> divergent thing has been going through words at a rate of one every decade or two, though the last step has broadened the category enough so it might stick (but will almost surely trigger the introduction of a new term because sometimes you need to be more precise).

There can be a brief period where people use the new word but subconsciously haven't updated their connotations (I'm assuming)...but then the subconscious figures it out (I'm guessing) and the brain's all, "Oh, I guess we pronounce 'retard' as 'special' now, unlike that other meaning of 'special'! No problem, we're awesome at context!"

The path to an actual increase in compassion and/or understanding is mostly unrelated, though I do think that if you're otherwise perfectly situated for a sizable compassion/understanding-boost, changing the language can help speed it along.

However, I think you've only talked about half of what "woke" means in practice--the easy half, where you stand for everything that is so good and right and pure that only demons would oppose you. (I have chosen this phrasing to suggest what the other half is, and why it is problematic.)