You need to wonder if the singapore government is making the right moves by pandering to an increasingly vocal xenophobic section of the populace. For a start by reducing the gap between PR and EP, the govt itself is devaluing the PR. End result, people will be wary of making long term commitment to singapore.
Secondly by making mid level and low level jobs, exclusively for singaporeans, you will end up with 90% of foreigners left here making a ton of money and a majority of the locals in middle class jobs. (My definition of middle class jobs is >$60k and < $100k pa salary) Result is a more wider gap between the locals and foreigners and yet more resentment with foreigners living in condos
and driving cars while the average middle class singaporean is living in an HDB and having to make do with public transport. This would be a powder keg just waiting to explode.
Thirdly with the reduction of foreign workers in low-level jobs, you wonder who would do the jobs that singaporeans don't want. Construction, cleaning, Low-level maintenance, Retail jobs, F&B wait staff, Front line Customer services. All jobs which have nearly 0% of singaporeans. Will employers hire singaporeans (if they even show up for such jobs) or will they overwork their underpaid foreign workers to take up the slack?
And finally once the industries do not find enough skilled local resources to take up key roles that don't pay enough to justify hiring a foreigner, and they start looking at alternate locations like Jakarta, KL, HK etc, will the government step in to fill the gap in number of jobs lost?