Very true. All of the characteristics of fabrics tend to get exaggerated. All materials have limitations. You have to know how to deal with them.
As far as durability of fabrics, there are many, many ultra durable synthetic fabrics. Cordura is one, woven nylon (if used in the same thickness as other clothing) is extremely durable, not to mention more exotic materials like cuben fiber which is one of the strongest ever developed. GoreTex is just a membrane. How durable or thornproof it is depends entirely on the fabric to which it is bonded. It can be made extremely durable. GoreTex and eVent, when bonded to a strong material are both waterproof and thornproof. Sympathex and ToddTex are other examples of durable and waterproof materials used in alpine tents, designed to handle extreme stresses. There are literally dozens of others. Both my Arcteryx shell jacket and Mountain Hardwear pants are synthetic and extremely durable. I use them when pheasant hunting, which consists mostly of walking through thorn bushes all day long.
I'm not sure why anyone would want a material (natural or synthetic) that is warm, waterproof, breathable and sparkproof. Seems like it would make for a horrible layering system. I'm not familiar with any natural materials either that meet that criteria. Cotton is not sparkproof, not waterproof and not warm. If it is made waterproof, it is no longer breathable, equally not warm, and even less sparkproof. Wool is not waterproof, and it is notoriously non durable or thornproof.
But let's be honest, the average bushcrafter does not do anything which would even come close to pushing the limits of any clothing system. Most can go out with their pajamas and will do just fine at a regular meet. If you want to really compare clothing, look at people who truly rely on that clothing. Go over to UKClimbing and see what people use. Go see what triple crown holders use. That is where the differences between clothing systems start to make a difference.
Here is an old trip report, but one of my favorites. It has an excellent discussion about gear by a guy who has now done several trips to Denali:
http://www.ukclimbing.com/gear/review.php?id=3994 Not all of the recommendations are needed for a relaxed trip in the local woods, but it is a good reference point.