I agree a 2025 SRD with the latest iteration of 5e is necessary − and is a good will gesture.
The DMs Guide wont even finalize until 2025, so I dont expect anything sooner.
I am curious why 3e needs attention. The 3e is already available. One can translate all of three into 5e using the 5e CC. Or oppositely, use the 5e CC to retroclone 3e. Since WotC no longer actively supports 3e, I am unsure why they should invest energy in it.
By contrast, WotC needs to release a 4e CC, since that actually is unavailable to fans. Options like Warlord and Swordmage remain legally awkward. Unless WotC plans a 5e Warlord, it would help to let fans make their own.