I don't think so, in Napoli's latest match, Lukaku was not in the squad, instead of playing Højlund, Conte preferred Lorenzo Lucca as a starter. Napoli's next match is against Fiorentina & it's not impossible that he'll feature in that crucial clash. It would also be an opportunity for him to prove to Conte that he belongs at Napoli. But back to my initial thoughts, I'm not sure Højlund will play. It might take some time for Conte to get him back into the side.
If he does, it wouldn't be unfair, because he's a new player. He needs some time to gel with the players. It would be unfair to expect him to perform at his best. Sometimes, not playing a player can protect him. Conte might be doing that.Currently, Hojlund has officially become a Napoli player, registered in Serie A since 01.09.2025. And according to the latest news, he will be included in the UCL squad, and could be in the lineup for the next Serie A match against Fiorentina. And as you said, it's the first week, and we can only hope for the best possible outcome, but we can't force him to perform that well straight away. But if he can do it, it will be a plus point that will have a big impact on him.
Source: Rasmus Hojlund has been included in Napoli's UCL squad