It's Normally expected that if you implement IEquatable.Equals you will also override Object.Equals to be consistent. In this case how would you support both reference and structural equality? = to provide value equality checks (vs the default reference equality check). The MSDN documentation suggests you only do it for immutable https://c-object-kullan-m07394.like-blogs.com/27943906/c-istructuralequatable-nerelerde-kullanılıyor-aptallar-için