It is interesting just how many of today's supposedly "new and revolutionary" products and methods of applying technology are rooted in the variety of those early days.
Standardizing on one platform appears on the surface to be more efficient, but may not be beneficial to the trade or the individual developer long term. In fact, blindly doing things the same way time after time can obscure better ways of doing things. I appreciate the fact that by coding for many of the systems the parent mentions, I have gained perspective on different design and architecture decisions. This has proved invaluable when working on a number of software development projects throughout the years.
Variety is good.