A second advantage is that a loan unlocks the cash in your home. It could come in handy, especially if we don't have the anticipated V-shaped recovery.
One more thing: Switching from an HDB loan to a bank loan looks smart on the surface, but I advise against it. If interest rates rise, bank interest rates will rise faster than HDB rates.
HDB also has a heart. It won't repossess your flat if you miss a few monthly payments. Banks are likely to do so.