I agree with you overall, but while it was relatively simple, DQN was never "elegant". The elegant and most important part of DQN was to use a CNN for learning a good image representation - but CNNs are completely unrelated to RL.
The sole contribution of DQN was to introduce two ugly band-aids, experience replay and a target network, to make the CNN training stable in an RL setting.
So, DQN = CNN (elegant and simple) + ugly band aid
The sole contribution of DQN was to introduce two ugly band-aids, experience replay and a target network, to make the CNN training stable in an RL setting.
So, DQN = CNN (elegant and simple) + ugly band aid