Sadly, with an entitled attitude issue that you are exhibiting, then maybe your last comment is your best bet. You didn't do a search of our huge archives before posting? That's was the search engine is for. You come here with you hat in your hand and then rail at the answer you receive when you don't provide sufficient information.
Singapore gave you a job that you admit pays you an over average salary at the expense of a citizen in all likelihood. They do not owe you anything. You didn't give them anything, including your youth. Nothing was stopping you from leaving. In fact, they put up with you and allowed you to continue to take a Singaporeans job for 15 years.
You may, along with other issues we don't know about, be of the most crowded demographic (for PR applications) with the smallest allotted numbers and the highest salaries/academics. But because you don't supply us all the necessary general information, we can only give you answers/opinions based on what you give us.