100NL is not easier than 50NL, unless you have super table selection skills and can identify/find tables full of donks.

However, there are a lot more decent aggressive players who will make your life much harder. It's not that they're not beatable, but they are a lot less predictable and more aggro than players at 50nl, and, most importantly (IMO), they won't fold nearly as often to your c-bets and bluffs.