You are most certainly going to feel the 'hacker'ness of blockchain, as most of the development tools are rough around the edges.
As for the developers actually working in the field, most of them have a background in either web development or a low level language like C. It really depends on what part of the stack you'd like to work on.
You'll get a sense of what the smart contracting language is expecting of you. Most of the development is still standard front end web dev with web3 hooks to the blockchain. So besides a basic understanding of how blockchain works (Mastering Bitcoin is a good start), understand how to code a basic web application and you're off.
>the difference between building a billion dollar company and building a 10 million dollar company is marginal.
That's not even remotely true. Building a billion dollar business is a much different experience than trying to build a $10 million dollar business. It's not a simple difference of scale, it's a difference of kind. What you're saying is kind of like saying that playing high school football and playing in the NFL (or Premier League for our European friends) are only 'marginally different'.
I get this from two working experience: one with my family business (valued in the 8 figure range) and one with a start-up shooting for a billion dollar valuation (which is our actual stated goal). The difference is palpable, but the biggest difference has to be with the opportunities we choose to pursue. The family business tends to have a pretty solid understanding of the market we're in. We know who we are, who our competitors are and we choose our targets carefully. This has led us to profitable, sustained growth. At the start-up, we were going for crazy opportunities and saying yes to very challenge projects, something the family business would have said no to. Why? Because the start-up has to get 'lucky' and find an unexpected opportunity that propels us forward. We need this because there is no other way to get to $1 Billion valuation than through crazy growth, which if you're a start-up means working crazy hard and getting lucky.
As for the developers actually working in the field, most of them have a background in either web development or a low level language like C. It really depends on what part of the stack you'd like to work on.
If you're just looking to get started, check out the solidity docs and open up remix in your browser: https://solidity.readthedocs.io/en/develop/
You'll get a sense of what the smart contracting language is expecting of you. Most of the development is still standard front end web dev with web3 hooks to the blockchain. So besides a basic understanding of how blockchain works (Mastering Bitcoin is a good start), understand how to code a basic web application and you're off.