I agree with this assessment, except that as a person who specializes in scaling Drupal I tend to be familar with the more common problems, and not too intimida

I agree with this assessment, except that as a person who specializes in scaling Drupal I tend to be familar with the more common problems, and not too intimidated by them. In addition, you can now buy fairly scalable hosting from Pantheon or others. I would add one comment: most projects fail because they don't get written, and they never get to the stage where scaling matters. Thus, I would focus on picking a tool that will allow you to get your project to the minimum viable product stage as cheaply as possible.