For me user expectations and whether you actually have the resources to produce a quality SPA are the biggest deciding factor. I don't have a strong opinion on

For me user expectations and whether you actually have the resources to produce a quality SPA are the biggest deciding factor. I don't have a strong opinion on SPAs in the general case, but I find it worrisome that it seems that SPAs are used as the default starting point without considering if the gains actually outweigh the cost. E.g At my last job I build the initial version of the application alone and although I'm pretty confident in my javascript skills I opted for a traditional server-side app too keep complexity and cost of maintenance as low as possible. Javascript was later added on top to make common interaction like sorting a table feel more responsive.