That's a bit like saying auditing/compliance is something that you might as well let the accounting department take care of. It's certainly true that making sure you're compliant with various regulations is a large part of what someone in accounting does, but it seems pretty clear that you can't let the same person be the auditor as well without a conflict of interest, and that's roughly what the role of a data protection officer is all about.
There's some evidence that data protection authorities share this view; a German authority fined a company after they appointed the IT manager as their DPO[1] (sorry, German-only source). It might be too early to say for sure how this will play out, but I wouldn't gamble on data protection authorities accepting just any IT employee unless they're working in some very specific role that prevents any conflict of interest.