Comments Outrank Reactions by a Wide Margin
LinkedIn treats a comment as a substantially stronger signal than a reaction, and the reasoning is the same as everywhere: a comment costs more. Writing two sentences in public, under your own name, in front of your professional network, is a materially different act from tapping Like.
The effect shows up in how long posts live. LinkedIn will resurface a post in the feed when it gets new comments, sometimes days after publication. Nothing else on the platform does this as reliably. A post with a conversation running under it can still be circulating a week later, long after an equivalent post with reactions alone has disappeared.
That longevity is the main practical reason to buy comments here rather than reactions. Reactions get a post moving in the first hour. Comments keep it moving afterwards.