Total BS IMO. Use whatever you like, but use it wisely.
Totally agree with Denny (as per usual).
Long ago I learned to take any
recommendations like the one the OP encountered with a shrug. I particularly reject suggestions not to use specific ingredients and if anything, am prompted to go ahead and experiment with those ingredients.
Individual experimentation is the only thing that provides a definitive answer. Otherwise, you may missing out on an ingredient you really like the contribution of...be it a malt, a hop variety, an adjunct sugar, or other ingredient...and you'd be missing out just because it wasn't to someone else's tastes.