As someone who did this sort of things in Boy Scouts, this is not super-simple just using natural materials. Maybe you're superman but starting fires with just natural materials was actually very difficult for our ancestors for a very long time. And is difficult today.

I'd invite you to watch the show Alone, where many survival experts have had to give up in the first day or two because they opted not to bring a fire steel and don't want to freeze.

You're right that it's possible, but how long it takes, and whether or not you can do it, are dependent on skill and environment. Wrong kind of wood? Screwed. Been raining for a day? Screwed. Sometimes this can be overcome, but you have to know what you're doing, and it can still take hours to generate enough heat to dry the wood until it's possible to friction combust it. Try it sometime, just bring a lighter with you.

A fire steel is probably the simplest low-tech way to start a fire. You still need some expertise like finding a mouse nest or other flammable material even if it's been reasonably dry.

But friction methods are tough, even if you have a well-made spindle and fireboard--which of course require tools. You're not easily creating those without tools to make those tools. And, even then, it's not super easy especially in a non-optimum environment.