So, it will not be an ideal Bitcoin tourist attraction for people with Bitcoin to visit, because you will have to pay with Fiat currencies for goods and services in Singapore.
But maybe, there will be a lot of merchants or shops that will accept bitcoin or crypto payments. I believe, they can be a bitcoin hub even if they don't make bitcoin as legal tender. As long as bitcoin payment is readily available in most of their services so tourists can actually use their satoshis anytime they want to. And with the settings in Singapore, I believe they can easily do it. But that is, if merchants are also willing to add bitcoin in their payment system.