>>28379936>>28380014The established timeline is unchanged.
Yes, remakes replace the originals, but the timeline is not changed at all. There's even a bunch of stuff in OR/AS the re-establishes it as being at the start of the timeline, just as R/S/E were.
FR/LG can be canon with OR/AS. Until stated otherwise, we have no reason to believe the events of Gen 1 happened any differently in our new Canon.
Like you said, remakes replace the old games. Nothing else changes. Why would it? That would effectively make it so that every time there is a new Gen, or remake game, everything else before it is "non-canon" because they don't acknowledge the changes in the newest game. That's a very silly mentality to have. It's be like saying the original Gen 1 was a different canon to Gold/Silver, because of the lack of Steel typing.
Also, you seem a bit confused about the idea of multiple canons. Game Freak only ever follow the one. Multiple dimentions/version differences as a concept is canon, but Game Freak doesn't care past that. They just make the games/timeline as they go along, and all the games fit into it fine, provided you're using the most recent version. (Pic Related)