I may be wrong; but, I'm never in doubt.
I think the problem with clothing failures such as this are due to poor-fit of the article for the person. If a person splits their pants, it is because the pants were too tight. With casual wear, the seams might be strong enough to transfer the stress failure to the fabric itself. Sometimes the seam will fail, sometimes the stitching. In every case, the article will be too small.
Mass-produced clothing patterns are made for an average (not normal) body shape. The standard-sized article may or may not conform to the shape of our body resulting in one or more stress areas. Ideally, standard shapes can be altered to custom fit us. The result is a stress free fit that will wear evenly, all things considered.
As evidence, examine your clothing. Notice that the pieces that show undue localized wear will be tight-fitting. It is no coincidence that loose-fitting clothes will never show the kinds of failures for what you now blame on the fabric, its care, the activity, and the brand (cut).
Some might say, 'lose weight,' but that is misdirected. Rather, try loosening-up a bit and even bicycling every day won't show appreciable wear.