I strongly believe that both orders are correct. "Upgrade/disable add-ons after product upgrade" means upgrade/disable CMS addons, which take no affects with EPiServer Commerce 7.5.
I agree this can cause some confusions, we'll take a look to see if we can improve it.
The Commerce SDK has conflicting documentation when it comes to order of upgrade steps.
Under "Knowledge Base\Upgrading" and "Upgrade procedure":
Under "Knowledge Base\Upgrading\Upgrading Enoteca based sites" and "Upgrading steps in deployment center":
What is the correct order of these steps?