I wonder where they measure from, as it claims >1 second of loading time for what is ~500ms in my browser. And my browser is also absurdly slow, now that I loo

I wonder where they measure from, as it claims >1 second of loading time for what is ~500ms in my browser. And my browser is also absurdly slow, now that I look at it. The HTML at https://lucgommans.nl https://lucgommans.nl is 978 bytes, the CSS 2KB, and the ping 39ms. With DNS+TCP+TLS+HTTP, the HTML downloads in 159ms. And then it waits. And waits. Then, after 134ms, it decides that DOM content has been loaded and fires the DOMContentLoaded event (there is no JS on the page). And then it waits some more, until after waiting 177ms it decides to start downloading the CSS which finishes in 44ms. And then it waits again for 40ms, downloads the 33KB background image in 80ms, and finally clocks the total loading time at 508ms. How fast should it be? The loading times are 283ms altogether (sequentially), how long does parsing 3KB of data take on a modern CPU? Close to zero right? I remember in iirc ~2007-2015, quite regularly there would be news that browser X had optimized the DOM parser, or rewritten the JavaScript engine, or cut off some time with this or that. What even is going on here, did all this go out the window with the multi-process browser where it has to talk to other processes to get things done, or what's up with all this waiting? Does anyone know?