That article misunderstands cheating. In the example given, grifting players in the clam market is in no way cheating. It is playing the game well. Does the author also think bluffing is illegal in poker? Goodness.
On the other hand, probably there is some clause on BGA that says that looking up words on Google is against the rules so its quite obviously cheating.
Incidentally, there are ways to cheat in many games on BGA. For example:
-In Carcassonne, there is a tile counter website you can use to card count, so you don't have to do it with your brain.
-In Fluxx, you can pretend its your birthday when it's not, and then you get extra cards.
-In any game with more than two players, you can collude with others.
Unfortunately, banning achievements/arena in Hardback doesn't follow suit with BGA's overarching stance on cheating. For example, arena mode is disabled in Chess, which makes sense, because a Chess engine will play the whole game for you. Its not disabled in Carcassonne, because even if you are using the tile counter, you still have to make decisions on how to play yourself. Hardback is the same way. Even if someone is cheating to look up words, they have to decide which pieces to purchase and how much ink to use, and so forth. You can't play the whole game via an engine.
TLDR: Turn achievements and arena back on for Hardback. Doesn't make any sense disabling it. Some will cheat and some won't, who gives a shit?