So many here quick to excuse this blokes appalling behviour and look for things other than him to blame.
A plane is a form of public transport that means you will be travelling with others in close proximity especially in whY. One shouldnt expect to have unbroken (or realistically any) sleep in whY, so when you are inevitably woken you need to shake it off.
If you cant cope with someone reclining then book an exit row or bulk head or higher class. Whilst i think we'd see less air rage if airlines removed recline in whY, its a known annoyance.
Walking around the cabin arguing / harassing crew or other passengers is not ok. Biting someone is not ok.
We know this wasnt a couple of seconds of disorientation after waking, the articles all say his behaviour was over an extended period long before he was recorded.