The Bolt has 3 coolant loops. Out of curiosity, I popped the hood and felt the temperature of them after driving 25 km. The battery one was indistinguishable from ambient. The powertrain one was maybe a few degrees above ambient. The HVAC one was mildly lukewarm (because interior heat came on this morning a little). I do not anticipate this vehicle putting much stress on the coolant or any of the hoses or fittings!
I understand GM's decision to not bother trying to recover waste heat, because it looks like there isn't much to recover. When there is high demand for interior heat (cold start), there isn't battery or powertrain heat to be had. If it's really cold, both battery and interior are going to want heat. When battery has surplus heat (supposedly during DC fast charging in summer), or powertrain has surplus heat (probably fast driving in summer for long periods), the interior doesn't need it. KISS...3 separate systems, each one simple.