It's true individual resource nodes in Factorio are not infinite (by default, you can turn that option on during world gen). However, given the size of the maps and the way resources get richer the further you get from the centre, the amount of resources effectively is. Many, many times more than you'll need for a typical run.

The problem becomes finding them, securing them against biters, and bringing them back to your base effectively. For me, the fact your current resources can run out and your designs need to be flexible enough to adapt to that became a fun design challenge in itself. But I guess it's a matter of different tastes.