I hadn't heard that theory before, but that would actually be pretty neat. Didn't the Triforce turn into birds or something at the end of the linked Oracle games?
Yeah, that would make sense. I've held the interpretation since the BotW sequel trailer that Calamity Ganon was likely just a coalescence of malice escaped from Ganondorf's body combined with Sheikah technology, and imbued with his destructive nature but not intelligence.
I think this is true in the early stages, and Nintendo in general aren't ones to let lore get in the way of a mechanic or concept they envision. But there has been a definite tendency since Ocarina of Time to contextualize the story of every Zelda game in relation to another Zelda game. Majora's Mask, Wind Waker, and Twilight Princess are all direct story sequels to Ocarina of Time in different ways, the Four Swords subseries has an internal consistancy regarding Vaati and the Four Sword, The DS games have continuity with Wind Waker, A Link Between Worlds is explicity linked to LttP, etc.
Breath of the Wild is pretty notable because it bucks this trend and seems to intentionally obfuscate how exactly it ties into the overall storyline in the series, but I do think they didn't completely throw canon to the wind. The game has the most callbacks to Skyward Sword of all games, with the continued emphasis on Hylia, allusions to Fi in the Master Sword, and having several direct geographic references. Since the world, engine, mechanics, etc. are mostly done already, I could see the story getting more of an emphasis this time around and dipping back into the well of Zelda lore, especially as the de-emphasis on story for BotW was one of the aspects that was criticized.