Canonical is not a multi-million dollar company, they’re not Red Hat and I don’t even think they’re a profitable company yet. If they had the money to produce a prototype before the campaign, I believe they would have.
The handset itself is not that important. If they can’t raise enough money they will ship Ubuntu on some other device and still get what they wanted to achieve.
As for the software, yes, they are reinventing the wheel, but so are FirefoxOS and Tizen. There are currently 3 big players in the mobile OS market (Android, iOS and Windows), 2 of which are completely locked down, so why not bring a few more open platforms in the party ?