Especially the last one is just a painful reality of the process. I think it's somewhat similar to the scientific method in that regard. Often your hypothesis is just false, but that does not make the attempt less valid.
To me this is one of the differences between making a wheel for learning or a wheel for innovation, as I mention in the blog. The latter can truly be reinvention, while the former is indeed often more like simply making your own wheel.
Yes, it has to be balanced appropriately. I didn't emphasize this a lot in the blog post, but this is really important in a work setting, compared to when working on personal projects. I still think wheel-reinvention has its place in professional teams, but the related challenges should be taken more serious in that case.
Especially the last one is just a painful reality of the process. I think it's somewhat similar to the scientific method in that regard. Often your hypothesis is just false, but that does not make the attempt less valid.