#3345 merged on 2023-01-27 and shipped in VS 2022 17.6 implemented #2924 WG21-P2404R3 Move-Only Types For Comparison Concepts for C++23.

In llvm/llvm-project#99420, libc++ considered implementing this downlevel in C++20 mode. On 2024-07-25, I commented in llvm/llvm-project#99420 (comment) :

I would be fine with changing MSVC's STL to align with making this a de facto DR, if libstdc++ is also on-board. This doesn't take any new publicly-visible names, and it seems like a highly compatible change (Annex C lists a theoretical break but you have to be looking pretty hard for it).

On 2025-12-01, Wakely concurred in llvm/llvm-project#99420 (comment) :

I have no objection to treating this as a DR, we can do the same for libstdc++.

As the Majestic Three are in alignment, let's make this a de facto DR.