Because the open module is only for Turing or later GPUs, or Ada, and the open module is available for those since 2022 so it’s not that big of a news.
For now they didn’t share nothing about it!
Tho in the roadmap for plasma 6.5 (https://community.kde.org/Plasma/Plasma_6) you can find:
No GPU acceleration still?
There is kmail tho it’s not the best, far better to use something like thunderbird!
The 980Ti as stated by the Dirk’s comment use Maxwell architecture, I’m not able to find any end of support date on the site, so I’m not sure when they will drop support.
Unfortunately you don’t need to wait to see this happens, because it’s already happening right now, indeed dx12 games have a lot of problems running on this older cards on linux, and I myself experienced this with my 1060 first with cyberpunk 2077 and after that with resident evil 2 remastered.
As even stated by doitsujin (dxvk creator):
Source: https://github.com/HansKristian-Work/vkd3d-proton/issues/465#issuecomment-744092867