In a perfect form of WoW I might be entirely against LFD. A game without boosting, botting, gold buyers, meta slaves, proper gear balancing, etc. But since WoW is not that, and Blizzard has no concern for the integrity of the game, then LFD probably should be added.
LFD is hugely beneficial to new players, and players who “require” gear from certain dungeons. It’s actually anti-fun to whisper dungeon groups and get ignored/denied because of the class you are or the gear you have. It’s so anti-fun as to make someone consider quitting the game.
People say “just find a guild” as if the majority of guilds are anything but raid loggers. Even in the best guilds on a server you might be hard-pressed to find a “guild group” to run dungeons with on a daily basis.
If any change should be implemented to LFD it should be that it does not award additional gear/xp/items over finding a group another way, and perhaps it should also require that a player click on the summoning stone in order to start a queue for the dungeon. Beyond that, punish players who leave an LFD group early by preventing them from joining the queue for an hour.