I think you need to prepare yourself for disappointment then.
'Legacy wide, not character specific' seems pretty clear to me. If you can see ambiguity in those words I fear it is entirely the product of wishful thinking.
I'm not agreeing, as of yet. Character specific can also mean the decorations. If I defeat the Dread Masters on my main all characters in my legacy can use the resulting trophy. That's legacy wide, not character specific. It was never said, specifically, that Strongholds could NOT be individualised per character... just that they were legacy wide. Like a Legacy wide character perk to unlock. If you have a quote that's more specific, I'd like to see it.