It seems that it is often the case when you have two competing technologies that everyone wants to pick a side.

This tech is better at this thing, but this tech can do it in this other way and is better for these reasons. As developers, we should instead be interested in what best suits the needs of the current job, and more than that what suits you as a developer for the current job.

Rails v’s Sinatra is a similar argument in my mind. Both are good technologies, both are web servers, there are some few cases where one has a definitive advantage over the other, and numerous cases where - depending on your background and personal preferences - you could choose either. I personally use Rails more than Sinatra, as I find the opinionated framework usefully, ever when only rendering a single page, others feel different. This is not to say that I have not chosen or will continue to use Sinatra for certain application.

My main point here is that each of the technologies is a tool that we as developers can use to solve a given problem. We don’t all need to solve that problem, in the same way! While it is true that some solutions will