A big factor in that “tinkeriness” of SPAs is how nearly every part of making an SPA well-behaved and pleasant to use falls almost entirely on the shoulders of

A big factor in that “tinkeriness” of SPAs is how nearly every part of making an SPA well-behaved and pleasant to use falls almost entirely on the shoulders of the developer. Due to how little browsers provide on that front, well-behaved polished SPAs are very much not on the happy path or default. Even if you use the big popular libraries, special care must be taken to not build a product that’s a frustrating mess for users. In comparison a server-side MPA will probably be at least decent to use unless the dev has been entirely careless, because that model better matches what browsers have been built for. The takeaway is that for SPAs to be consistently good for both devs and users, browsers need to do the bulk of the heavy lifting and provide a “happy path”, largely eliminating the need for overwrought JS libraries that try to paper over browser inadequacies.