Google operates at such a scale that tiny increases of performances allows them to support a team of engineers and saves money on the bottom line.
For example, Google hires 10 engineers, they deploy HTTP/3, it saves 0.5% cpu usage, Google saves a million dollars and covers the salary of the said 10 engineers.
For the vast majority of society, the savings don't matter. Perhaps even deploying it is a net-negative with a ROI of decades. Or, the incentives can be misaligned leading to exploitation of personal information. For example, see chrome manifest v3.
It absolutely matters. Machines are orders of magnitude faster than they were 20 years ago; most software isn't doing much more than software did 20 years ago. And no, collaborative editing isn't be-all, end-all, nor does it explain where all that performance is lost.
Many optimizations have bad ROI because users' lives are an externality for the industry. It's Good and Professional to save some people-weeks in development, at the cost of burning people-centuries of your users' life in aggregate. And like with pollution, you usually can't pin the problem on anyone, as it's just a sum of great many parties each doing tiny damage.
>most software isn't doing much more than software did 20 years ago
This isn't exactly true, but some of the potential reasons are pretty bad. Software turning into an ad platform or otherwise spying on users has made numerous corporations wealthier than the gods at the expense of the user is probably one of the most common ones.
For example, Google hires 10 engineers, they deploy HTTP/3, it saves 0.5% cpu usage, Google saves a million dollars and covers the salary of the said 10 engineers.
For the vast majority of society, the savings don't matter. Perhaps even deploying it is a net-negative with a ROI of decades. Or, the incentives can be misaligned leading to exploitation of personal information. For example, see chrome manifest v3.
It's okay to question whether we need it.