The Streacom SG10 case from Computex 2023 demonstrates, that passive cooling is possible for high-end setups. However, the SG10 looks like a big case, and many people might not want that, or like me, do not have enough free space. A PC desk on the other hand can use more space for cooling, since components can be positioned under the table. Considering a height-adjustable desk, cooling could even be built into the feet. Current PC desks, like those from Lian Li (https://lian-li.com/product/dk-05f/), also look a bit gimmicky to me, and a sleek passive cooled alternative could appeal to a wider audience.
My idea would be to combine a skeleton for a height-adjustable desk without the table, and the passiv cooling concept from the SG10, but spread across the desk for better cooling. This way, people can choose their own desk appearance. Additional bonus would also be reduced cable management, since the PC is already integrated into the desk so no more cables from case to desk.