When your approach is "I don't care because I have more important things to focus on", you never care. There's always something you can do that's more important to a company than optimising the page load to align with the TCP window size used to access your server.
This is why almost all applications and websites are slow and terrible these days.
Performance isn’t seen as sexy, for reasons I don’t understand. Devs will be agog about how McMaster-Carr manages to make a usable and incredibly fast site, but they don’t put that same energy back into their own work.
People like responsive applications - you can’t tell me you’ve never seen a non-tech person frustratingly tapping their screen repeatedly because something is slow.
To add to this, bloated performance is often 'death by a 1000 cuts' - ie there isn't just one thing that makes it slow, but it's the cumulative combination of many individual choices - where each choice doesn't incrementally make that much difference, but the cumulative effect does.
ie if you have 100 code changes, each one adding 'just' a 10 millis - suddenly you are a second slower - and yet fixing any one problem has a minimal effect.
> This is why almost all applications and websites are slow and terrible these days.
The actual reason is almost always some business bullshit. Advertising trackers, analytics etc. No amount of trying to shave kilobytes off a response can save you if your boss demands you integrate code from a hundred “data partners” and auto play a marketing video.
Blaming bad web performance on programmers not going for the last 1% of optimization is like blaming climate change on Starbucks not using paper straws. More about virtue signaling than addressing the actual problem.
SPAs are great for highly interactive pages. Something like a mail client. It's fine if it takes 2-3 seconds extra when opening the SPA, it's much more important to have instant feedback when navigating.
SPAs are really bad for mostly static websites. News sites, documentation, blogs.
Well, half of a second is a small difference. So yeah, there will probably be better things to work on up to the point when you have people working exclusively on your site.
> This is why almost all applications and websites are slow and terrible these days.
But no, there are way more things broken on the web than lack of overoptimization.
> Most of us are aiming for under a half second total for response times.
I know people working on that exist. "Most of us" is absolutely not, if they were so many, the web wouldn't be like it's now.
Anyway, most people working towards instantaneous response aren't optimizing the very-high latency case where the article may eventually get a 0.5s slowdown. And almost nobody gets to the extremely low-gain kinds of optimizations there.
"More than 10 years ago, Amazon found that every 100ms of latency cost them 1% in sales. In 2006, Google found an extra .5 seconds in search page generation time dropped traffic by 20%."
This is why almost all applications and websites are slow and terrible these days.