Apple is not known for good web services. The App Store being a fork of iTunes Store and the Mac App Store building on the same unstable foundation. Sure they are getting better and better, but still...
Apple will want to scale this from the web or from on-device apps. Previously we've seen that Apple is detecting each part by serial number, so even mixing genuine parts disable a lot of features [1]. So, now it becomes clear part of their reason: If they can detect all the genuine parts, they can ship for self repair and it will work for the intended customer and not for other devices. This reduces chances of cloning, theft and scams, while guaranteeing quality (and guaranteeing their revenue on replaced parts too).
IMO, yes, it would require years for them to announce this. There is all the checkout part, they would need to issue the right part with the correct serial number to the exact customer and charge taxes accordingly. All this logistics is centered on software Apple has a bad reputation at best, and very slow process of development from what is seems from the outside.
[1]: https://www.youtube.com/watch?v=8s7NmMl_-yg