The Apple instructions have been incorrect for some time..... I've sent feedback on this more than once suggesting they change the wording..... This does happen sometimes with Apple's instructions. As the Terms of Use here require it is best to try it first before posting.
For whatever they are worth I offer the following comments.
I have re-read the Apple instructions again and agree that they should be revised. IMO they are not technically incorrect per se but they are misleading. The current version states under the section "Unlock your iPhone":
1. Back up your iPhone.
2. When you have a backup, erase your iPhone.
Would be clearer if that sentence said: "When you have a backup, restore your iPhone using iTunes and when prompted, set the iPhone as New, not From backup." Apple may believe that the wording "erase your iPhone" is analogous to "set up as New" but this is not clear to all.
3. Restore your iPhone from the backup you just made.
Would be clearer if that sentence said: "After you receive a message that your iPhone is unlocked you can restore your iPhone from the backup you just made."
Likewise the current version states under the section "Get help":
1. Restore your iPhone to factory settings.
As above, revising to include "setting the iPhone as New" would be preferable IMO than "Restore to factory settings" (even thought the two are synonymous).
2. Contact your carrier to make sure that the unlock was applied in your carrier's system.
3. Restore your iPhone from a backup.
As above, revising to "After you receive a message......." would be preferable here as well.
You mentioned that you have sent feedback to Apple more than once suggesting a change of wording. Would it be worth it to try again ???
Regarding the Terms of Use, I do not want to get into semantics here but the wording they use is not "require", it is "when possible". I have tested most of my suggestions when possible. I am not willing to drop my phone into my pool in order to advise an OP that placing the phone in a bag of rice could help, or similarly, I am not willing to click on a phishing webpage and enter my credit card in order to advise an OP that they should contact their cc issuer and clear their Safari history and data. I also do not test Apple's Approved Publications, it is the job of their engineers to do so.
Thank you for your help in clarifying this procedure, as I mentioned to the OP on my previous post, it was you who solved her issue.