I have read that many people, in countries that have repressive governments, use bitcoin to move their money out of the country.
You mean governments use bitcoins to move their money out of the country ?Are you confusing yourself ?Wrong information anyway.
It seems to me that the bitcoins of the future need to be untraceable by governments to be useful to the public.
Bitcoins are not fully anonymous.Read the post by GMaxwell that makes much sense.Also,it's not *bitcoins of the future,just coins.
Which altcoins are being developed that could fill this need? These might be the altcoins to watch. Such altcoins would probably not need an exchange, nor want one to remain non-traceable.
Only coin I could think of right now
https://zcoin.tech/