ECC was probably not for consumers. I think they needed to have an offering for processors smaller than E3 for pro needs, and somehow merged it with some i3. Also check for embedded options: those are basically LTS, so low volume and/or high latency designed specialty electronics can use them without having to update all the time. I've not checked if there still are some offering on some newer gen i3, but Intel can very well have internal restructuring between their consumer and their pro-branch, which I remember having read are not very integrated...