Mess what up exactly? AMD has managed to stay in this game against all odds and still be competitive while also pursuing other lifelines very successfully (like semi-custom). That the average Joe lacks the perspective to understand this is another matter. It's also important to be clear about whose perspective you're asking about. For you, perhaps, you'd see Vega as a fail. I doubt AMD shares that opinion.
Ultimately, what matters for the average Joe (who reads these sort of forums/reviews) will be price & performance. As for the 99% of other average Joes, it will come down to marketing & sales. And THAT has been AMD's historic and biggest weakness. All the hardware details and the like are important to the very few very nerdy people who care about such things (like me) but ultimately isn't what's moving inventory.
Look at the story of the AIBs for example. Why is it that Asus manages to sell their GPUs for so much more than the others, while not delivering an objectively better product (noise, cooling etc)? There's but only one answer - branding. We can only hope Intel manages to poach even more of AMD's "talented" marketing department because AMD could sure do without them & with some different ones. Maybe they in turn can try to steal some of Nvidia's. What they did with RTX was genius, even though in reality it's at best a gimmick right now, they managed to plant a seed in gamers' minds for needing RT, and therefore Nvidia cards, especially as they tied DXR & AI "supersampling" to the RTX brand. AMD needs to do things like THAT.
On the technical side, they just have got to keep card variation down, like Nvidia does. The current stacking of V56 Pulse performance for £250 & V64 Nitro+ for £350 would not be too bad if that's what Navi looks like, and they bring down TDP & add ray tracing; and must have HDMI 2.1! Essentially that would be very competitive, as it also is right now, but would also allow better margins for AMD and perhaps allow for discounts further down the line if Nvidia responds in kind.
Either way, I wouldn't expect much from Navi itself. We're already spoilt for choice & this is very much a transition period in gaming graphics. I think the big leaps are still yet to come, perhaps 2-3 years from now.