I've always described what I do as marketing for developers at the end of the day. Developers typically have the thickest bullshit shields and know immediately when they are interacting with someone that isn't technically credible - say at a conference expo booth.

I've personally had very little involvement with sales over the years and have mostly operated at the top of the funnel. Most (from my experience) DevRel teams actually sit under a marketing org.

They used to call it Technical Sales in the circles I travel.

Tech Sales is focused on closing accounts, whereas Dev Rels do things like teaching developers how to use a company's APIs at hackathons. It's like the difference between conversion marketing and brand advertising.

Not just (nor even mainly) 'the customer'; they talk to 'the community' first and establish their employer's bona fides to the market.

The main difference I would say is the emphasis on the backpack they wear