The good news here is that Adobe suite is not really threatened by Affinity products, as they're ahead in terms of features and enterprise presence.
They acquired Figma because Figma was quickly becoming the go-to collaborative UI design tool in the workplace, something Adobe did not have with AdobeXD. If they were to try to acquire another company in this space, it would likely be Canva, rather than a comparatively small player like Serif.
Consumers/the free market told Adobe to fuck off, but Adobe ignored them and forced their way in by buying the competition. This is something they've consistently done throughout their history, and it doesn't seem like there's anything consumers can do about it.
FreeHand is probably the most high profile, if not well known nowadays, since it led to a lawsuit brought by pissed off ex-FreeHand customers (which ultimately ended in a shitty settlement).
They acquired Figma because Figma was quickly becoming the go-to collaborative UI design tool in the workplace, something Adobe did not have with AdobeXD. If they were to try to acquire another company in this space, it would likely be Canva, rather than a comparatively small player like Serif.