I would hope that they are going for a two tiered approach. Keep Canva for amateurs to compete with other low cost online design options, and use Affinity to compete in the professional space. Tying them together in some way would allow users of both skill levels to collaborate on a project. Say the pro designer can log in from Affinity, and the customer with the cheap/Free Canva. The customer can just move a thing and pick a color, then describe the more challenging parts to the pro. Or something like that. I use Affinity for my side gig....I don't want to lose it.
While they may, I doubt it. That would be doubling the efforts. They would have to keep both separate, they don't even live in the same space code wise. Even the download app is really nothing more than a webview based on what I saw. I would have to wonder if they do keep both around long term, I would bet Affinity goes full web and is no longer a native app. While I don't mind and have used browsers for UI on some of my apps, they still were local, I don't see any of that coming in the future for most commercial apps as it is (the joys of always thinking newer tech is the way forward).
I could easily see one gets parted out and eventually disappears (I saw nothing in their response that would give me confidence long term, unless I missed something in later responses, which is possible). Have to bare in mind there is a bigger customer pool going for the "normies" versus the pros (even some pros are just "normies" with bigger pocketbooks).
As to the hardware stuff out there, pucker up, it's going to get worse in that world as well (if one could even imagine that happening).