I think it must be a link if you would expect user want to open in a new tab, no matter it pushes history (navigation) or replaces history (in page tab). There

I think it must be a link if you would expect user want to open in a new tab, no matter it pushes history (navigation) or replaces history (in page tab). There are countless of times that middle click to open new tab didn't work because page author use <button onclick="location.href='xxx'> as link. It's such an awful experience.