Wow, the fact that you compare Reddit to HN, and you consider the Reddit SPA to be "better" means you have a fundamentally different notion of better. For me, Old Reddit and Hacker News load fast, feel snappy and native, and work better in every way, while the new Reddit SPA is sluggish, full of random network errors and bugs that I encounter regularly just clicking around, and takes up a ton of memory/CPU just to browse a discussion site.

And Reddit's frontpage size is 1.3 MB according to one check I did which checks the size of all network calls after loading, etc. and that's WITHOUT all the lazy-loaded content below the fold.