Demand isn't high because so many more people prefer to rent - demand is high because it's the only financially viable option. Why is it the only financially viable option? Because landlords (both corporate and personal) buy up all the property they can and rent it out. Because so many houses are getting bought as rentals, the supply of houses that can actually be bought is low.
Seriously, have you spoken to anyone who has tried to buy a house in the last few years? Every single one I know had a myriad of stories like "I put down an offer, but some investment company offered $20k over asking, cash in hand"
And because housing prices are so high because of the above behavior, more and more people are forced to rent, who would have 100% been able to buy a house not that long ago. And so rises demand.
If what you were saying was true (that rent prices are high purely because people love renting, and no one wants to be a homeowner), then why are we seeing sky high home prices at the same time? You're quick to pull out a half baked supply and demand theory, but you're very quick to ignore the other side of that equation.
Also, more fundamentally the whole "supply and demand explains all commerce" thing has been thoroughly untrue for ages. Maybe in a world without giant multinational conglomerates, political corruption, and price fixing. But in the real world, things are wildly more complicated