Thank you very much for your answer @mvaneijgen, very precise and the comments as well as the links to the documentation are much appreciated!
If I understood your solution correctly, it would be possible to separate the title animation in two? Like after loading the title appears at the end of the first timeline, while a new one with a ScrollTrigger manages the scrolling and the other animations of my page?
Sorry for my stubbornness or if my question looks stupid, but it's really nice to have people to talk about it!