https://forum.square-enix.com/ffxiv/...812-06-2020%29
They put up official digest translations of their liveletters in a very official manner. Even in this digest, they reference this:
"The normal version of Delubrum Reginae will be required to complete story quests, and is similar to alliance raids in terms of difficulty."
"Players can upgrade their weapon after completing all 5.45 quests."
Considering the liveletter talks about new story quests in Bozja....it's impossible to interpret it any other way.
Even beyond that, the reddit discord has extremely powerful translators that not only do live translating, but also go back and solidify the translations later to clear up any doubt. bozja's story being required to progress the relic has been telegraphed for literal months now, both in an official and non-official manner. Anyone needing to have information cleared up has both an official source and non-official source both saying the same thing in 95% of cases.