Go is a great choice these days pretty much exclusively due to the tooling. Turns out having a good compiler that's really, really fast is a big deal.
My main issue with prototyping as a concept is that it doesn't exist in most workplaces. Prototypes quickly devolve into applications. Discarding code is risky. Your best bet IMO is choosing a language that's ergonomic in the long run, because odds are you're in for the long run.
dotnet is another great choice because of the tooling and batteries included, although you do have to deal with a fairly slow compiler. Java is okay too, but Java is very restrictive and high-friction, which might not lend itself to prototyping.
In the world of scripting languages, ironically PHP is a decent choice. It has better progressive typing than Python and it's reasonably safe these days. We've sort of come full circle on PHP. The downside is that PHP programmers tend to throw everything in an array, especially when going fast. That hurts readability and the IDE a lot.
And then, of course, typescript and node. I don't like typescript. There's something about scripting languages with build steps that pisses me off. But, it's got a wide developer pool and it's not the worst language ever. Although there's a bit too much teeth-pulling IMO with typescript.
I do think there are some inherent tradeoffs in the space.