If Neymar is cut from the national team, there will be a lot of rage against the coach from the brazilian crowd, because he is still the favorite player in Brazil, the one most brazilians like and want to see on the field. If he can't help brazilian national team, he won't cause any prejudice too, so there is really no point in replacing Neymar by another athlete who can't deliver the same or similar performance results.
Moreover, Neymar has been involved in political polemics as well recently, so a removal of him could configure arguments of political persecution inside the country against him, as he was a supporter of the previous president Bolsonaro, who is the main opponent of the currently president Lula, having the left wing supporters already tried to "cancel" Neymar, without success so far.
As I said, it's not a popular opinion and it would certainly be controversial, but in my opinion, as we're talking about the 2026 World Cup, it might be necessary to think about the team without Neymar.
With so many controversies and injuries, it's not hard to imagine that there's a good chance that in 2026 he'll be injured or unable to play fully
And another important point is for the coach and the team to get used to it without Neymar, because he's the team's great reference point, when he gets injured Brazil can't play as well yet, but it's a question of changing the style of play.
There's no shortage of good players who can help the team, like Vini JR or even Endrick from Palmeiras, who is 17 and will be 20 at the World Cup, he could be very important for Brazil
I don't think that's going to happen, but I can see that point