Let's start with my biggest obstacle; Walmart's return policy. You could buy that Hyper, take it for a spin, decide you don't like it, and they'll take it back. I'm not going to do that. I'm sure there are a lot of people who are just wary of used stuff, so I'm down a point here.
Another potential advantage to the Hyper, is that it's a 29er. It really shouldn't matter to the kind of casual cyclist I'm looking for as a buyer, but maybe they've done some research and know that 29" wheels are the new hotness in cycling. Even though they really aren't anymore. If nothing else, 29" tires are probably easier to get.
Finally, the Hyper has a disc brake on the front. What brand? I have no idea.
And I think that's it for the Hyper's advantages over this 25 year old Iron Horse. I am 100% that all the parts on the Iron Horse will work better, and stay working better for far longer than what's on that Hyper. We're talking Falcon rear derailleur, no name brakes, 7speed shifters, stamped steel chainrings, non-sealed threaded (?!) headset, no-name 'suspension' fork, and bolt-on wheels.
We've also got a Shimano 1x9 drivetrain - no need to worry about finicky front derailleurs.
I've equipped it with some Serfas semi-slick tires - gravel tires if you're 35 or younger - which I think is perfect for Kelowna, given all the gravel trails out here.
As a mechanic, professional and otherwise for 40 some years, I guarantee the Iron Horse will be a better experience, I just have to find a way to convince buyers of that.