Are you referring only to embedded links, or are you including inline/contextual links?
I like seeing links that establish context, whether they are external or internal (e.g., pointing back to earlier articles by an author). Most of the time, I don't click on them. Many times I just ignore, unless there is compelling reason to dig deeper.
As for embedded links, for me it also depends. I tend to just skip--almost as if the embeds re invisible--unless there is context being established.
As for top writers not using these embeds, perhaps the reason is that they've already reached that level that there is little incentive for self promotion. For someone still starting out, there might be experimentation on whether such links or embeds can increase their exposure.
I do agree with you that it should not be spammy. For me, context is key in determining whether a link or embed is necessary or extraneous.