Not sure if it will help. The reason I suggest this is when I go to level up my crafting some, I chug a xp pot and go to town making shards. Then when it runs out, I go over to the deconstructor and destroy all the shards I created to get some of my essence back.
I'll have to do a video capture and post it, but seriously devs, try it. Make like 50 stacks of shards, in amounts of 1-4, and then go to the deconstructor and break them down. After a while, the lag is unbearable.
I dunno if it has something to do with the animation sequence that happens when you click the button to deconstruct or what, but it did seem like if I tried to go quick and put a new shard in the machine before it was done with the animation that it exacerbates the situation.
Not to mention doing this infrequently locks up the machine where you can't put another shard into it and have to close it and reopen to continue.
I know in one of the videos I believe it was mentioned that a cannith crafting revamp was slated, with lowest priority, for this year. However, could a dev play around with disabling the animation and see if this helps alleviate the issue short term?