Intelligent Design or Irreducible Complexity is essentially an argument from incredulity. That is, I don't understand it - therefore my much "simpler explanation" must be true.
Argument from incredulity - RationalWiki
More traditionally ID, IC and their ilk is a form of "God of the Gaps." If you can't explain it, some supreme being must have done it.
God of the gaps - Wikipedia
Both "Argument from Incredulity" and "God of the Gaps" are intellectually lazy arguments.