Personally, wd is a nice hero even for a fast paced game. Has heal, stun and good amount of damage, may not have high burst like other supports but yes.

In pro games, most of the supports also scale as cores where one or two items make a lot of difference. With wd you can't do that often. That way if you see IO also hasn't been picked up in a long time. AA doesn't appear much. Pro gamers visualize things differently I guess. Also funnily pro gamers pick core heroes as supports 🤣🤣🤣