Note that, the extensions points are being completely revamped now. 
p1895r0.pdf
p1665r0.pdf

and others.

On Tue, Feb 4, 2020 at 10:50 PM Daniel Gutson via Std-Proposals <std-proposals@lists.isocpp.org> wrote:
What people think about this?

struct S
{
    std::swap(S&, S&) = delete;
};

In this example, this would be useful to prevent std::sort for example (even if we add operator< ).

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Who get stuck with all the bad luck?
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