Can you tell me what advantage there is for a European player to go and play for a country like that and be naturalized in Indonesia? I think that if there was the possibility, everyone would do the opposite. I don't think they would want to have only Indonesian citizenship. I think that playing in Europe is already a great privilege for a few, so they would do well to stay where they are.

Actually, this goes back to the quality of the players because if they stay in Europe or meaning waiting for a call from the national team in their respective countries with the quality and competitiveness to enter there then they do not have the opportunity or even if they are called they will probably only fill the bench that's why they choose to be naturalized because there is an opportunity to be a starting line up and play against other countries such as the case done by Indonesia because it can be said that most of the naturalized players do not have the opportunity to play in the main national team.
I agree with you. Perhaps this is why these players want to be naturalized to become Indonesian players. They realize that their quality makes it difficult to compete or be called up to their home national teams, so they use other countries to gain access to the national team through naturalization. Or perhaps they believe in Indonesia's vision for football's future careers and potential for development.
I'm Indonesian, but what I see most clearly is that naturalized players here are "celebrated" as athletes. This is something they may not experience in their home countries, as you said, because there they struggle to compete.
Furthermore, naturalized players in Indonesia easily become famous, have a loyal following, and receive many gifts and presents. Furthermore, their social media following skyrockets, and support floods in. This is what I see in the phenomenon of naturalized players in Indonesia. I prefer Malaysia's strictness in setting requirements for players seeking naturalization.