Absolutely true. But some things are universal. For example there are few climes in the world where you don't need shelter at night no matter the season. And fire is a near-univeral need for cooking and water purification. No matter where you are on this blue marble, you need oxygen to breath, a means to regulate your core temp, water to drink and food to eat. Honestly, those things would also apply on Mars; it would just take different gear to provide for them.

I'm a fan of both Dave Canterbury and Cody Lundin. Dave preaches that for survival, you take tools. Tools are hard to make in the wild. With tools, the rest is just a matter of effort and calories. Cody emphasizes using what you have instead of looking for something you can use. Both approaches make sense.

Ultimately it was training that saved the couple in question. Knowledge helped them first by ensuring they packed a minimum of useful gear. Then it saved their bacon by teaching them how to use it.

I think you're better off with a couple pounds of gear tailored to your environment and a lot of knowledge of how to use it than someone with a 70 lb pack full of random "survival" and camping gear they don't know how to use.