No. Just no. You’re talking about perfectionism basically. Who cares about continuing maintenance? If you get the product out there and working enough to last the 2 years warranty, you’re completely fine. One programmer is perfectly capable of learning the most basic things about the disciplines you mentioned, it doesn’t need to be good, it just needs to do its job mostly.
You have no clue about the scope of what this guy’s idea is since he gave no info. Maybe it’s so simple not even one programmer would have to work on it for very long.
Of course, what you say is perfectly possible to be “correct”, but you just have no way of knowing.
Ideas are incredibly cheap. It’s absolutely unlikely that no one ever had your idea. It’s even likely that someone had your idea and it failed, and you don’t/can’t even know about it because no one bothered to record the failure.
Other people have mentioned all kinds of ambitious/proper ways to do this. I’ve got a different view: if you truly think this will work, do a basic version yourself.
Learn basic blender, design 3D printed parts yourself and let someone print them. Use some app builder and tutorials, or hire a programmer for a very rudimentary prototype work. Buy generic electronics. Just get it working once. Then show it to people, let them use it, ask if they would buy it, preferably let them sign a slip of paper not to talk about this product or compete with it (there are standard NDA/non-compete contract clauses online available) or talk to people you can trust.
If you do all this and get positive feedback, then you can start doing this properly and get more people on it, like the other commenters mentioned.