"It all sounds lovely until the universe turns into a cold, dead cinder." You are assuming heat death is inevitable, however this may not be the case, in fact

"It all sounds lovely until the universe turns into a cold, dead cinder." You are assuming heat death is inevitable, however this may not be the case, in fact if it is possible to harness Zero Point energy as energy and matter are just two sides of the same coin it will be possible for us to avoid heat death, that would certainly be a Revelation and humanity would be the Saviour.