I do not think there's a convergence at all tbh. I mean if we're going to use references as evidence for this, there's a lot more weight carried by games like Triforce Heroes and Spirit Tracks that have references to the entire series in them as well. That isn't to say it's without merit, but rather you shouldn't look to it as something to suggest the timelines are converging.
I know a bit about the Zelda timeline myself, and I've more or less done this off and on for years, but...here's what I get from what we know about Breath of the Wild.
Now, this wouldn't be placed in no ordinary position, but let's look at it his way.
The Wind Waker was supposed to take place near 1000 years after Ocarina of Time. Twilight Princess is more along the lines of 100 years, and Four Swords Adventure probably takes place after another 100 years as well. And then you have the Downfall Timeline, which by and large between their games is likely at least 100 or a couple hundred years. So what would happen in the Child Timeline, if left alone by evil forces for nearly a millennium? Ganon was sealed inside the Four Sword itself, leaving the kingdom available to be at peace for a fairly long time. Kokiri stilled evolved into Koroks (like they did in Wind Waker), however instead of a new culture created by the sea, it was instead a culture based on technology.
Without Ganon, technology flourished. Hell, we already seen a bit of this in Twilight Princess itself, which had a pretty good era of peace in between it and Ocarina of Time.
My theory is this, more or less: Breath of the Wild is to the Child Timeline what the original Legend of Zelda was to the Downfall Timeline and what The Wind Waker was to the Adult Timeline. All three games take place in post-apocalyptic worlds of sorts, but due to different circumstances (LoZ: Terrorized by Ganon for centuries. BotW: Great civilization fallen by Calamity Ganon. TWW: Hyrule flooded to destroy Ganon.) yielding different results. All three games are fairly open-ended as well, allowing you to pretty much explore the world as you please even though it takes a little bit before you get to do that in Wind Waker.
I know a bit about the Zelda timeline myself, and I've more or less done this off and on for years, but...here's what I get from what we know about Breath of the Wild.
- The Master Sword's location - The only eras this could possibly take place in according to the Master Sword is sometime after Skyward Sword (but before Ocarina of Time and possibly even The Minish Cap), after A Link to the Past, or after Twilight Princess (and by proxy, after Four Swords Adventure).
- Koroks - This suggests some continuity with the Adult Timeline aka the Wind Waker timeline, however keep in mind that when Link and Tetra found a new land the Koroks were never seen again. Also, the Temple of Time AND the Master Sword as well as Hyrule itself is not in ruins, but rather it's buried deep under the sea never to be seen again. Ganon is also under the sea in the Wind Waker sealed by the Master Sword, with Malladus taking his place as the new Demon King as we see in Spirit Tracks.
- The Goddess Hylia - The only known point that we know of that people actively have knowledge of the Goddess Hylia was in the Skyward Sword era. However it's possible in a time unaffected by a large excess of evil to be able to keep a tradition such as Hylia alive, and neither the Downfall or the Adult Timeline really provide an oppurtunity for that to happen. Hell, in the Adult Timeline, the people of the Earth forgot the Triforce even existed!
- Landscape - While barren, there is defiinately signs of a previous ancient civilization that was highly technologically advanced. Even more-so than the ancient civilization the Robots were from in Skyward Sword. No game to date has displayed this level of technology, which suggests that this game MUST take place in a timeline where propsperity was strong enough to flourish AND allow the Temple of Time, the Master Sword, and Ganon to still exist at the same time. There is only one timeline for that...
Now, this wouldn't be placed in no ordinary position, but let's look at it his way.
The Wind Waker was supposed to take place near 1000 years after Ocarina of Time. Twilight Princess is more along the lines of 100 years, and Four Swords Adventure probably takes place after another 100 years as well. And then you have the Downfall Timeline, which by and large between their games is likely at least 100 or a couple hundred years. So what would happen in the Child Timeline, if left alone by evil forces for nearly a millennium? Ganon was sealed inside the Four Sword itself, leaving the kingdom available to be at peace for a fairly long time. Kokiri stilled evolved into Koroks (like they did in Wind Waker), however instead of a new culture created by the sea, it was instead a culture based on technology.
Without Ganon, technology flourished. Hell, we already seen a bit of this in Twilight Princess itself, which had a pretty good era of peace in between it and Ocarina of Time.
My theory is this, more or less: Breath of the Wild is to the Child Timeline what the original Legend of Zelda was to the Downfall Timeline and what The Wind Waker was to the Adult Timeline. All three games take place in post-apocalyptic worlds of sorts, but due to different circumstances (LoZ: Terrorized by Ganon for centuries. BotW: Great civilization fallen by Calamity Ganon. TWW: Hyrule flooded to destroy Ganon.) yielding different results. All three games are fairly open-ended as well, allowing you to pretty much explore the world as you please even though it takes a little bit before you get to do that in Wind Waker.