We disagree on RAW, not on RAI.
The sentence: "You can't use magic items." implies that you can use normal items. The implication comes from english, and as such is part of RAW.
The same way the sentence "The dragon can’t use Breath Weapon again for 1d4 rounds." implies that the dragon can use Breath Weapon after that. The RAW reading of this sentence contains the implication and no one states that, per RAW, we don't know if the dragon can breath again after 1d4 rounds.
You're trying to defend a specific way of reading english that would be RAW. But English is not a programming language and as such carries a lot of implications. Ignoring the implications makes your reading wrong, not better.
This rule is unclear. Per RAW, as it comes from the way it's written. That's why people start speaking about the intent, because we can't determine the rule directly from the way it's written and stating that the rule is clear is nearly insulting. We should stop the discussion about RAW and English, as it's a rabbit hole, and quite an obvious one.
Given that PF2 is very much a permissive set of rules that only allow for actions covered by said rules, your reading it as an implication simply doesn't make sense. In point of fact, PF2, as written, cannot imply things that don't have bespoke mechanical interactions because it doesn't give us any means by which to resolve an implied rule. Furthermore, I doubt you could find any other 'implied rules' without torturing the meaning of what is written as you are attempting to do here.
Your reading of RAW is wishful at best and malicious at worst.