I measured an LCP or 3.5s + significant layout shift. The images are poorly optimized jpegs, instead of WEBP/AVIF. The start page takes a cool 6MB. A games page clocks in at around 12MB before the video starts loading including a whopping 4MB JS. None of the links appear to utilize preloading and it's and old school multi page app, so navigation takes a long time. I don't have a way to measure it, but subjectively it performs worse in the Steam client than in a browser.