It doesn't cost $1000 even today, and as EV Code Signing certificates become more popular the price will fall.
A non-Code Signing EV certificate is "only" $100-200 right now from tons of vendors. All we need is for them to flag it for Code Signing which is "free."
Until you convince those CAs to start signing for code, they still cost $400+. And remember, that's per year. The driver will continue to function after that year, but they will either need to cough up another $400 the next year, or cease development. Even at $100-200 per year that's still an unreasonable cost for hobby projects.
Open source software of any complexity costs far more than that to develop, assuming you assign non-zero value to opportunity cost. Your time is valuable!