There are some mobile and desktop chips (they weere here even years before -> see the iMac computers from year 2013 and onward), that are using the much better Intel Iris/Iris Plus/Iris Pro series of GPUs, but for whatever reason, they are not featured in Apple's Mac mini computers.
en.wikipedia.org
Only Apple knows, if the will update the actual Mac mini (2018) this year. I think, they wont. Maybe next year in 2020.
However it is worth to wait 2-3 weeks, to see, if there will be a slight speed-bump, with the 9th or 10th generation CPUs.
Redefine the laptop experience with 10th Gen Intel® Core™ processors, featuring built-in AI, integrated Wi-Fi 6, and next-generation graphics.
www.intel.com