Every country has programs to improve its sport. Even though China failed to qualify for the 2026 World Cup, it doesn't mean they don't care about their football. It's just that Indonesia might have been luckier in the previous round, managing to beat China. As far as I know, at the Asian level, China's sport (in general, nit just football) was impoved, which means there are programs to improve football as well. However, Japan and Australia aren't weak teams that China can easily defeat, so that might be another reason why China failed to qualify.
However, the reason the Chinese national team’s performance has declined so drastically is due to several systemic issues. These include an underdeveloped football academy system, a lack of youth participation in pursuing football as a career, a domestic league recently shaken by scandals and the bankruptcy of many clubs, and the strong influence of politics, which makes players and coaches play too cautiously out of fear of being punished by their president. All of these factors combined are causing serious problems for the Chinese national team at the moment.
If they had been able to better maintain their football ecosystem from the start, perhaps these problems could have been avoided. Chinese football once enjoyed a golden age, with massive club investment and government support, which even attracted world-class players. However, corruption, dependence on investors, and various scandals have damaged their football ecosystem, and the impact continues to this day.