Dividends don't decrease your tax burden. The reason why you get
a tax refund back is because, the profits from the company was
already taxed at the company's tax rate of 20%. Since your personal
tax bracket is lower than 20%, IRAS just refunds the difference
back to you.
BUT, they are doing away with this tax refund thingy. As such you
cannot claim back your tax difference and you will be tax at the
company's tax rate of 20% instead of your personal tax rate (which
is much lower, unless you make mucho mucho money).