The argument that "because others are doing SPAs, we have to do too" is invalid, the "others" are just either your friends or popular JavaScript programmers, and you follow them because you lack better arguments to go against this development technique. An SPA adds unexpected behavior to every web application, when we have spent years learning how a popular web browser behaves, people come to re-invent the wheel (back buttons, custom scroll bars, custom routers, and who knows what else).
Normally, I encourage people to learn and work on whatever thing they are interested in, not just technology-wise. But when you start promoting your project trying to make people use it as if it was good, well, then you have to expect some rants here and there. I am sure there is a lot of people who would disagree with me, and people who have good arguments for the development of an SPA, I would love to hear those arguments, I am being serious.