It might. I don't have any prosthetics
per se, but I had to undergo some major reconstructive surgery in one of my arms a few years back after a bad accident. As a result, I've got a lot of "hardware" in that arm. Personally, I've always found the word "cyborg" a fun and interesting self-description, since, technically speaking, it's accurate. I'm also aware that I am a
lot nerdier than your average potential user here.
For a lot of prosthetic limb users, I imagine that preserving some measure of dignity is almost as important as preserving or attaining limb functionality. It's important to feel human, and to be taken seriously. "Cyborg," spun the right way, might have an empowering angle to it. But I could just as easily see it reading as glib and borderline insulting. I'm sure the founder intends for the former, but the market will determine which connotation prevails.
Whatever the case, I'm happy to see a YC entrepreneur in this space!