Maybe I'm naive but I'm not so sure Affinity will automatically end up as a subscription-based app like Canva Pro and Creative Cloud. Subscription makes sense for Canva Pro where a lot of the value add is in additional elements and templates and there's not a versioned app you can buy with a certain set of features. For a tool where you release discrete versions with new features it's a lot easier to just sell it as one-off purchases.

Even if Canva was out to milk Affinity for every dollar, the size of the market for the professional-level tools is a tiny drop in the bucket compared to the market for Canva-level tools. I can't imagine it would move the needle. But what do I know...