As someone that follows the space partially because it's a really cool story, I am amped about all of the attacks these days! It looks like there weren't any protocol failures or anything that made the attack easier. It's a simple case of 51% attack.
The hashrate for BTG is well below most other coins, a modest miner on another coin could easily switch and execute the attack, then switch back to their main coin and not have to pay large transaction costs for hardware acq or rental costs.
The hashrate for BTG is well below most other coins, a modest miner on another coin could easily switch and execute the attack, then switch back to their main coin and not have to pay large transaction costs for hardware acq or rental costs.