Is there any sense in hiking ultralight? Is it safe? Is it only for marked trails? Can you enjoy your hike if you discard many of the equipment you usually carry? Yes, yes, no and yes.
We live in a world of disposable things. That is extremely sad! On the other hand, there are outdoor products that last from father to son. Let's see some examples from my own hiking gear with a lifetime of 20 years or so.
I have used merino t-shirt every single day for year and two months now. I conducted a five months long test for Finnish outdoor magazine Erä last year, and after the test was published, I have continued using the same test shirts. What have I learned? There's a wish for merino shirt manufacturers in this post.