It always has been
Luffy is the main character the strawhats are his supporting cast each with varied relevance depending on the arc
Like look at the logo lol
It’s title is based on luffy’s dream, has luffy’s Jolly Roger that’s based on him, and even has a little luffy as the i lol
It’s always been luffy’s story. The strawhats have always prioritized luffy and his dream over their own
Even pre timeskip we had a whole saga where the other strawhats weren't relevant and it was just luffy. We’ve had hundreds of chapters were the whole crew was split up during dressrosa all the way to the start of wano. The only consistent thing being luffy the man character was around