Practically stars are mostly burned out in another 50 billion years and radioisotopes that produce a heat gradient will also be mostly decayed by then. Eventually good tidal energy situations like
will end as well since this kind of situation changes the orbits. So energy for life and usable thermal gradients will disappear even if entropy will continue to increase for a long time -- for instance, black holes will be slowly inspiralling and crashing into each other resulting in huge entropy increases on paper.
https://en.wikipedia.org/wiki/Tidal_heating_of_Io
will end as well since this kind of situation changes the orbits. So energy for life and usable thermal gradients will disappear even if entropy will continue to increase for a long time -- for instance, black holes will be slowly inspiralling and crashing into each other resulting in huge entropy increases on paper.