Specifically those languages are back end focused so about 28% of developers. 55 focus on front end. If you add up games desktop and mobile, oddly you get 28% as well. So not bigger but the same size good intuition! That leaves out embedded 8% and systems (8-12%). Which are probably more what rust is used for. There is obviously overlap and we haven't mentioned database or scientific programming at 12 and 5 percent respectively.
Edit: after rereading this I feel like I may have come across sarcastic, I was legitimately impressed a guess without looking it up would peg the ratio that closely. It was off topic as a response too. So I'll add that rust never would have an asynch as good as tokio, or been able to have asynch in embedded as with embassy, if it hadn't opted for batteries excluded. I think this was the right call given its initial focus as a desktop/systems language. And it is what allowed it to be more than that as people added things. Use cargo-deny, pin the oldest version that does what you need and doesn't fail cargo deny. There are several hundred crates brought in by just the rust lang repo, if you only vet things not in that list, you can save some time too.
Edit: after rereading this I feel like I may have come across sarcastic, I was legitimately impressed a guess without looking it up would peg the ratio that closely. It was off topic as a response too. So I'll add that rust never would have an asynch as good as tokio, or been able to have asynch in embedded as with embassy, if it hadn't opted for batteries excluded. I think this was the right call given its initial focus as a desktop/systems language. And it is what allowed it to be more than that as people added things. Use cargo-deny, pin the oldest version that does what you need and doesn't fail cargo deny. There are several hundred crates brought in by just the rust lang repo, if you only vet things not in that list, you can save some time too.