If you have time to read…
Disenchanting a card returns a very low (e.g. 1/4) dust return. IF you are sure that a card will never/see little play, then it make sense that the card can be dusted to get more value rather than sitting on the shelf.
Secondary concern is that that investment of dust for crafting. If dust is used to craft cards that can be replace with cheaper options, than it is a balance of how players are comfortable with the trade-off.
My no.1 rule is , If in doubt, don’t do it. (read up more/ask questions till you are sure)