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Traditional console/PC gaming will continue to dominate subscription services and cloud gaming for at least 15 years (truth be told, I don't know if those ever will replace traditional gaming). Sony and especially Nintendo will both be fine and won't find the need to merge or be acquired by anyone.
The only corporation that poses a threat to Sony is Microsoft, which after ABK's acquisition probably won't be able to acquire any major publisher, let alone a platform holder like Nintendo or Valve. If other giants like Apple and Amazon start acquiring publishers, the odds are they'd continue supporting Playstation, Nintendo, and Steam for a while.
I do feel that Apple is more than capable of making a successful "console/PC ecosystem" that can beat Playstation within a few years (if acquisitions + exclusivity is their game), but idk if they're willing to take the risks and initial losses which could be massive and cause the closures of multiple studios. On the other hand, if they keep supporting the established players, their new system won't take off, and they will exist primarily as a 3rd party software giant, which Sony would be very happy about. Actually, I can see Apple skipping the Xbox ecosystem, because Microsoft would be their direct rival who -after this leak- is very clearly planning to monopolize highend gaming. Apple can get Take Two and EA and skip Xbox/GamePass to promote their own subscription service, while supporting Playstation for those traditional software sales (as well as hurting Xbox console sales). And just like this, Sony wins without even trying.
If the other giants join this game, Microsoft may stand to lose more than Sony.
