This post here http://dndwithpornstars.blogspot.com/2016/10/temple-of-elemental-bickering.html discuss how elementals are boring, and they are. So are lot's of other monsters that have no consequence to the campaign, the link mentions a cool way to make sure there is a consequence even a brief one, when using a tool to upset the fabric of reality.
What are elementals anyway beyond a fragment of reality, just an incomplete sliver of what is and can be. All the genuine responses of an elemental should be rooted in their elementalness. A fire elemental is all about fire just like gravity is all about gravity, no one ever seems to spend much time wondering about the goals of gravity but it's always there, it's a building block of reality. Elementals are an embodiment of a predictable and known force. What is ultimately important and interesting about elementals is how they are used by DM's and players.
All monsters and NPCs are no better than what is put into them by the people playing the game. I'm a fan of monsters but the place of each should be considered if one wants to have a complex and involved campaign.
That fire elemental is pretty boring, if it is going to have a conversation at all it's likely (almost certainly) going to be about fire. Setting you on fire isn't good or bad to a fire elemental, it's all about fire. The consequences of the presence of the fire elemental is the interesting part.
I should have gotten more of this into my reply over at the blog in question but I didn't want to be rude and double post.