You can click into it to get the details; short answer is ‘integrated’, Intel discrete cards don’t even make it to the bottom, so less than 0.15% of responders.

https://store.steampowered.com/hwsurvey/videocard/

Adding up all the ‘laptop’ graphics cards comes to about 25% of the total. That would explain why the ‘median’ results for some of the metrics are relatively weak - 1920x1080 screen, 16 Gb of RAM. Be interesting if they kept laptops and desktops separately for those.