It would be for me, but like dikaiosune I've drunk the Rust koolaid almost fully by now.
But honestly, even if I hadn't it's be a selling point to me because it tells me that you're a place that isn't stuck writing everything in a single language but are willing to try new things are willing to use what seems to be the right tool for the job.
Well, sometimes depending on company size, number of developer developers, developer pool skill set, and many other factors, having a single (or very few) languages is a factor in the right tool. It's better when that's not the case though.
But honestly, even if I hadn't it's be a selling point to me because it tells me that you're a place that isn't stuck writing everything in a single language but are willing to try new things are willing to use what seems to be the right tool for the job.