Could anyone here tell me why, in practice, it isn't possible to write generic algorithms such as sorting or Red/Black T using interfaces only in GO ? It seems

Could anyone here tell me why, in practice, it isn't possible to write generic algorithms such as sorting or Red/Black T using interfaces only in GO ? It seems like having interfaces such as "comparable, equatable,etc" should work in theory. I've read somewhere that it was memory usage related, but i've got trouble picturing why (maybe an example would help)