For every 1000 people who know what your company/product is,
100 people will go to your website,
10 people will call/email your company to ask a question.
1 person will end up considering buying your product.
So build a dev advocate team, you will increase the amount of people who know what your product is/ask questions about your product. Furthermore people calling your company after interacting with a dev advocate isnt someone who just saw your logo, or heard what your company could do from another business person, but the people calling will actually know at least something about how your product works/interacts with the customers infrastructure. So the pipeline for interactions with people will likely convert to sales at a better rate than people from marketing/sales.
Dev advocates are able to talk about code (unlike most sales people), So if you able to convince a customer's dev team that your company provides value, you at least have some additional help convincing business people to buy your stuff if their dev team wants it.