Unfortunately im missing the "proton 9.0 Beta" and "Proton experimental" runner in lutris. I only see the "wine-ge-8-26-..." runner in the respective lutris runner tab.
Just two days ago i downloaded and nstalled a clean version via the official image-selector-website where those runners were out-of-the-box available.
I dont know which image i downloaded or installed two days ago. I used the image picker on https://bazzite.gg/ I am unsure if i maybe selected "Desktop" two days ago. Im am very sure that i selected "Home Theater PC" for the current installation.
Bazzite is a custom Fedora Atomic image built with cloud native technology that brings the best of Linux gaming to all of your devices - including your favorite handheld..
Solution
you can install it from the steam library if you enable tools in the list