Yes. There's eg combined power plants that use waste heat from power plants to heat houses. The problem is that this tends to make the power plants less efficient at electricity generation.
So this waste heat recycling should only be done where and when it makes sense.
(But that's pretty easy: absent any legal requirements, the involved parties have all the right incentives already. It's all internalised between the parties.)
> The problem is that this tends to make the power plants less efficient at electricity generation.
Huh what? Never heard of that one before.
> absent any legal requirements, the involved parties have all the right incentives already
Well... that's the problem, they don't. Sure, datacenter operators could go and offer to install district heating, waste heat recyclers and whatnot, and it would likely be profitable. But, and here it gets annoying, it's not profitable enough.