On the other hand, you might attract talent that wants to use a specific language like Rust, but hasn't had the chance in their current professional environment.
It's also worth considering what will keep the founder(s) motivated to stay focused and do good work. Yes, using JavaScript and Electron might be the optimal rational business decision, and in theory we should be motivated solely by the problem we're trying to solve. But if the technical cofounder, who's currently the only programmer, then feels that they're creating something that nobody can really love, and they get discouraged at the state of the world that led to that decision in the first place, that's not good for productivity. You can probably guess how I know this.
> what will keep the founder(s) motivated to stay focused and do good work.
I would not want to work with a cofounder who loses focuses when they don't get to use the trendy technology. They should be focused on delivering value.
That'd be a disaster for a startup. In order to use Rust efficiently, one needs to have a significant experience with it; without experience, one wastes a lot of time wrestling with ownership, lifetimes etc.
(I do program in Rust in my (non-trivial) hobby projects).
I've been toying with Rust on and off for a few years. It has an extremely steep learning curve. As a novice it's incredibly difficult to do things that are trivial in other languages.
> On the other hand, you might attract talent that wants to use a specific language like Rust, but hasn't had the chance in their current professional environment
Maybe if you're doing something embedded? Otherwise, the learning curve is so steep that you're better off just buying a faster computer to run C#/Java/NodeJS/Python/Whatever.
We've had 0 issues hiring for Rust, despite the vast majority of the company having no prior experience with it (or some experience on the side). The learning curve isn't that bad, maybe you just haven't dedicated the right time or you've had trouble learning it in isolation.