It has been added in there so it is ready for when it does come. You will also see that Wireguard is also there in the Connections WUI page. Those things are the relatively easy steps to do.
As you say there have been other post threads on wireguard
https://community.ipfire.org/t/inquiry-regarding-the-inclusion-of-wireguard-vpn-in-ipfire/10899/10
https://community.ipfire.org/t/seperate-appliance-dedicated-to-wireguard/12995/3
https://community.ipfire.org/t/inquiry-regarding-the-inclusion-of-wireguard-vpn-in-ipfire/10899/14
https://community.ipfire.org/t/wireguard-now-that-ipfire-is-on-kernel-5-10/6571/22
where wireguard has been asked for and donations to support us have been requested but as the last post in the above list indicates there has not been any real indication of interest based on the donations. So it will have to get worked on when free time occurs to apply some focus and time to it.