I don't think so, my forum is not using responsive design, only fluid layout but still get in top 10 Google first page with more keywords, responsive only is convenient for users using mobile devices.

According to Google the Traffic is increase in mobile Devices in 2014 insted of 2013 So if your site is not responsive than it not open properly in other devices.If your site Does not open good than No one see your site long time.

[DELETED]