10% rates at a digital bank

There's a digital bank that has been offering over 10% interest rate on deposits for months now.

How sustainable is this?

Looking at r/DigitalbanksPh, no one seems to be questioning where the money is coming from or if it's profitable for the bank. Everyone is just jumping on it.

Is this just a way for the bank to acquire customers? But once they end the interest promo, my guess is most would withdraw the money right away.