He literally relegated himself out of a major spotlight in favour of some unknown new leader nobody knows, and who no one will listen to.

You're not wrong. But he has wanted to step down for a while now, that is just the reality of the situation.

Yes, there now rests a democratically legitimized obligation on the British government, but article 50 hasn't been invoked yet and significant pressure might still be required to achieve that

It's going to be invoked. Anyone who doesn't think that is incorrect. The government is not going to ignore its own democratic referendum, not if it doesn't want riots, civil war like anger, and a lost of trust.

let alone on getting all the policies of decreasing immigration, increasing funding of the NHS (both of which are promises the Leave campaign largely retracted) and a mininal political union passed.

Yeah, a great amount of work needs to get done.

A long road still lies ahead, with many uncertainties and bumps in the road, and his leadership given his recent role is expected.

He's remaining a member of the EU parliament, the only place he has real power. He will be able to bully, negotiate, whatever here.

Farage never had any power in the government.

The campaign and his goal is far from being achieved.

Not really. They won the Leave option. The UK will leave. That was their core goal.

He will now probably hide behind whomever the nobody that becomes the new leader is.

I get that you don't like him, I didn't really expect the UK to leave either, but this is speculation that you have made up, not based on fact or reason.