This is the SG approach and we have not caught up in that aspect of innovation, and less labour friendly. Recall from people I know working in Australia, you can split it between 2-3 accounts, and it's the norm there, alom with getting paid usually fortnightly.
Not as simple as you think.
My company long ago use a customized system which can spilt. Then they changed to off the shelve system. The very expensive fully integrated SAP system. Cannot spilt.
For those who deal with IT systems, you will know best to keep it simple. It is fine to customize or modify if the need is crucial. Paying salary to more than 1 bank is not a need to the company.
Payroll system requires high maintenance. Every time CPF rules change, management change salary/OT policies, or bank make changes to their account format or file upload format, changes have to be made and extensive testing is required. You don't just test the area modified, full testing is required.
Allowing more than 1 bank account means need to have the database store multiple bank account with the ratio for each bank account. Have to make sure it spilt correctly to each bank account. Extra coding to ensure rounding difference otherwise may end up paying one cent more or one cent less and bank reconciliation to the financial accounts all mess up.
If I am the company, I won't do it because I have more important things to automate and improve that truly improve efficiency. Instead of pleasing a handful of people when maybe 99% of employees just need one bank account.