This value indicates whether this individual link is currently an active, contributing member of the port-channel bundle or has been excluded/suspended from it. It matters on one individual member link that participates in that internal port-channel bundle because a link can be physically up yet excluded from membership (for example due to a configuration mismatch), which would still leave it out of the bundle's aggregate bandwidth. A membership value of suspended on one link of this member link, even while that link's own operState shows up, explains a bundle carrying less aggregate traffic than its member count would suggest.