So if you see the point of a phone/watch as being to make PAYMENT easier, not to make CREDIT easier, going with a debit card opens you up to a lot more of the world. And yes, it is just a virtual wallet holding your virtual dollars. So what? That's what most people want. It's certainly how *I* use my credit card, as a payment card that I pay off religiously every month.
I pay off my credit card bills every month as well.
Here in Singapore, we have an app called Grab, which is a company that does ride-sharing, food delivery, and (recently) has a mobile wallet that lets you make payments via QR code. However, take-up rate is low, and if not for their rewards system, I don't think many people would bother with it, because having to open an app to scan a code is much more time-consuming than simply using contactless payment from your phone's lock screen directly (or even your Apple Watch).
However, I see value in the system allowing merchants to accept non-cash payments without having to manage an array of credit card scanners. Anyone can just print out a QR-code and past it at the counter and let the customers pay on their own. This makes sense in countries without a strong credit-card infrastructure (like China, which is how WeChat took off, because the country largely missed the credit card revolution). Conversely, this makes no sense in a country like the US, where credit cards are commonplace, and the fees are offset by the increased volume of transaction they supposedly enable.
And for me, it seems to defeat the point of using a credit card to top up another mobile wallet just so I can then make purchases from said wallet, instead of just using a credit card to pay for the purchase in the first place. In the beginning, there was the ability to double up on rewards, but the banks soon plugged that hole by changing their rewards system such that cash top-ups would not qualify for rewards.
Granted, Singapore is not the whole world, and there probably are many other developing countries where credit cards are rare and a mobile wallet solution could really take off. It's possible that companies like Samsung and Google are targeting these emerging economies where their cheaper android phones enjoy greater market share and it would be easier for them to push a mobile payment solution through their own software. The same way Apple makes it extremely easy for US consumers to apply for the Apple Card via the wallet app.
Else, I am not really seeing what Samsung can value-add at this point.