I personally think it's a reboot timeline that loosely reconnects to the others. The Zelda franchise has never been great about continuity or consistency and each game seems to take place in its own timeline (the LoZ multiverse). The references to the other timelines feel more like fan service than quality worldbuilding, and a lot of the different place names around the world feel like fan service to the familiar name from an older game rather than a logical location for that reference (which is in wildly different places in different games).
So, you think that the detailed history of Ruto being a Zora princess who became a sage that fought Ganon alongside the Hero of Time is ''fan service''?
Sure, place names are one thing since alot of them don't even make sense in context; for example, Mabe Village Ruins can't be the same ruins of the same village from LA, since 1) Mabe Village didn't exist in Hyrule, and 2) Mabe Village existed in a literal dream world. The example above is alot more concrete, however.
Also, sorry, but saying that each game takes place in a different timeline is factually wrong. There's always been a timeline since the second game was released.
-Zelda 2 confirms in game that it's a direct sequel to Zelda 1, taking place sometime after Link defeated Ganon. This game introduces the Triforce of Courage and the concepts of Ganon being able to be revived from the dead and multiple Zeldas to the lore of the series.
-ALttP is confirmed to feature the ancestors of Link and Zelda on the back of the NoA box and the NoJ box says that it takes place during an era before Zelda 1/2 Link accomplished his feat, during the time that Hyrule was ''one kingdom/country'' as per Impa from the Zelda 2 manual. It's also confirmed in the JP manual that says that the backstory of ALttP marks the beginning of ''The Legend of Zelda''. There's also a line from the JP manual that heavily implies that Ganon from the NES games is the same character as the one in ALttP. This game introduces the concepts of Malice, Ganon's backstory as a human man who became the Demon King, the Master Sword, and multiple Links to the lore. Unfortunately, all references to Malice were removed from the NoA version, though.
-LA wasn't given a confirmed spot in the chronology at the time of its release, but the manual says that it takes place after Ganon was defeated, narrowing it down to being either post Zelda 1 or ALttP, and one of the Nightmares takes the form of Agahnim at the end. This game introduces the idea that games in the chronology don't have to take place in Hyrule to the lore.
-OoT was confirmed to deal with the Imprisoning War backstory of ALttP, and features an even deeper look at the backstory of Ganondorf as mentioned in ALttP. This game introduces the split timeline to the lore.
-MM is an obvious direct sequel to OoT. Not only is it confirmed in interviews and ****, but the game itself makes it pretty clear, as it features the Hero of Time as a child after ''waging battles across time'',, and he has the Ocarina of Time in his possession.
-FS was confirmed to be the ''first tale'' by Aonuma at the time of its release. This game introduced the Four Sword and Vaati to the lore.
-TWW was confirmed to be centuries after the Link defeated Ganon as an adult in OoT. TWW constantly references people and events from OoT throughout the game.
-TMC is before FS, as it features the origins of the FS and Vaati.
-TP was confirmed to take place centuries after Link returned to the past at the end of OoT. This explains why TP doesn't refer to the EVENTS of OoT per say, but it does reference the Era of the Hero of Time(the ToT, the fisherman, etc).
-PH is an obvious direct sequel to TWW; the game opens up with a retelling of the events of TWW, and Tetra is in it. Besides, it was confirmed in interviews.
-ST is an obvious sequel to TWW/PH, as Nico is still alive as an old man, and Tetra is referenced. This game introduces New Hyrule to the lore of the Adult Timeline. It was also confirmed to be 100 years after in an interview, I believe.
-SS is an obvious prequel to every game in the series, due to Hyrule Kingdom not being establsihed yet and the MS not being forged until later in the game.
-ALBW is called TotG2 in Japan, and it was confirmed to take place generations after ALttP/LA in interviews.
-TFH was confirmed to be directly after ALBW.
-BotW is long after any of the games on one of the branches, but which branch hasn't been confirmed officially; we do know, however, that there has been multiple battles with Ganon in the world of BotW, and that Ganon has lost his sanity as per CaC, and that BotW is in a version of Old Hyrule where the OoT sages where awakened and remembered.
Only the Oracles, FSA, and to an extent BotW had unconfirmed placements at the time of release.