Performance
The discipline and practice of improving response time and computational load of websites.
The Cost of Javascript Frameworks
Javascript inherently is a massive percentage of a performance budget, modern frameworks are less performant than vanilla JS sites.
The Performance Inequality Gap
When we construct the digital world to the limits of the best devices, we build a less usable one for the 80+% of the world's users. A rule of thumb limit is ~100KiB of HTML/CSS/fonts and ~300-350KiB of JS (compressed).