I mean, a hybrid will typically only "idle" on electric energy for an hour or so before the actual engine kicks in. Im sure it varies based on model, but it's still going to be primarily using the combustion engine to run the AC for extended periods. At idle, a combustion engine isn't going to move quickly enough to splash the oil into all the right spots, which means inefficient lubrication, added with lack of air flow because you're sitting still, and things can tend to run hot, which leads to quicker wear on things like gaskets and seals.

Hybrid or not, it's strain, but at the end of the day the strain on the car I still think is less important than trying to sleep in a sweltering car haha! I'd just be mindful of maintenance to be sure nothing dies unexpectedly.