That's a great point, if we consider the many-worlds interp…

That's a great point, if we consider the many-worlds interpretation in the context of time travel, it's possible that every point in time is a separate universe or branch of reality. This would mean that if you were to travel back in time, you wouldn't be altering the original timeline, but rather creating a new branch or universe.
The concept of a base timeline becomes somewhat ambiguous in this scenario. It's difficult to define a single, objective timeline as the "base" or "original" one. Instead, every branch of reality could be considered its own separate timeline.
However, some theories propose the idea of a "prime timeline" or "main trunk" that serves as the origin point for all other branches. This prime timeline could be thought of as the initial, unaltered sequence of events, and every time travel event or decision creates a new branch that diverges from this main trunk.
But here's the thing: if every point in time is a separate universe, it's possible that there is no one "true" or "base" timeline. Every branch, every reality, is equally valid and exists independently. This would mean that the concept of a single, objective timeline is more of a human construct, and that time travel would allow us to navigate and explore different branches of reality.
It's also worth considering the Novikov Self-Consistency Principle, which proposes that any events that occur through time travel have already occurred and are therefore predetermined. This would mean that if you were to travel back in time, you would only be fulfilling a predetermined course of events, and not actually altering the timeline.
What are your thoughts on this? Do you think the concept of a base timeline is still relevant in the context of the many-worlds interpretation, or do you think it's more of a fluid, ever-changing tapestry of reality?