As for Sicilian, I can sort of understand , even though it still isn't that important to pick something else, but one can do so.
Most beginners start with 1. ...e5 against e4 as this type of symetry have the most sense for someone starting out. That being said, 1. ... e5 is very complicated on the highest level as well.
One of the things he recommended was French, which is theory heavy as well. But, it is still okay if one likes it.
Exploring openings you like is ok as well. For instance, I am kind of decent with black pieces in the Sicilian, while I didn't enjoy it as much with white, and I started playing Moscow/Rossilimo as white as a result.
In any case, as long as one likes his opening lines and is not lost, it is completely fine to continue.
I think what @Compadre_J is getting at is that a lower rated player may have more success with a more simple opening. I'm only picking up the sicilian now at 1700. Before this I played the caro.