That’s what solar energy does when it hits the ground or the oceans. It turns into heat or evaporated water. The latter is why it rains.
Harnessing it and piping it through extra steps only to end up as heat does nothing to the planet’s heat balance. All human energy use is tiny compared to total global solar flux. Like not even 1%.
The data center water issue is a municipal management problem. The problem is that evaporative cooling is cheaper. If data centers are using too much water to the point that it’s causing problems for homes or agriculture, it means they are not being charged enough for that water. Charge them more and they will suddenly shift toward more closed loop cooling.
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2008EO28...
Waste heat from human energy use is a real problem, it does influence Earth's temperature, minimally for now, but it will only grow. And it will be MUCH harder to solve than global warming.