40 years ago this problem did not exist in Indonesia. Food purchased outside the home was wrapped in banana leaves or served on reusable plates, items purchased from the market were carried home in reusable woven bags or slung in a textile sarong, and garbage was mainly organic in composition so biodegraded quickly.
Plastics changed everything. Now, plastics make up >20% of the waste stream, and the typical (and this is a generalization which does not reflect pockets of 'green behaviors') Indonesian mindset leads to the disposal of waste as if it had the old organic composition. Indonesia is drowning in plastic.
The $1 billion announced is a start, but represents just $4 per Indonesian citizen. Nowhere near enough to reverse a problem 40 years in the making.
It took Western countries 20-30 years of steady, social engineering just to begin to show success from "don't litter" campaigns, so the challenge that Indonesia faces is huge. And for the commenter who suggested that Indonesia has to raise it's standard of living first before dealing with plastic waste, what do you think happens as disposable incomes rise? Yup, more plastic waste per capita is consumed and disposed of as people buy more 'stuff'.