If you’re meaning our Wallpaper Contest for 22.10 we did talk about it early in the cycle (ie. in the days after 22.10 was released) but decided not to run one for this cycle.
Anyone can submit entries for possible inclusion anytime, as you’ll see in this thread where a user submitted some created wallpapers, which was then used in our Lubuntu 21.10 release (both for sddm or the greeter background, and main wallpaper/background), with the greeter also being used in our Lubuntu 22.04 release as well (sddm or greeter only).
We have the images we expect to keep for our upcoming Lubuntu 23.04 release (see here), with them already viewable on our daily ISOs.
Thank you for your enquiry, and please, if you have any submissions you think would suit Lubuntu, just submit them as my example by @fahim.