Why wouldn’t it feasible? I thought people such as yourself brag about how much money they make and that they can buy all the resources they want?
Of course Apple can excel in all their respective areas if they manage and listen to the right people. They don’t have that many fingers in pies. They have certainly exceeded in some areas and performed abysmally in most others. IMO, one of the main issues is they prioritize retail considering most of their staff is retail.
Apple excels in using their control over hardware, software and services to produce a superior user experience that consumers are willing to pay for. This doesn't mean that their hardware, software or services are necessarily the best in their respective fields, but that when put together, the end result is more than the sum of their parts.
For instance, there is that YouTube video of Jonathan Morrison showing how he can edit 4k videos on a Macbook running FCP. This is an example of how optimised software can make up for seemingly mediocre hardware, leading to a better experience than the specs would otherwise indicate.
Likewise, take the Apple Watch for example. Through the control Apple exerts over its platform, Apple has put Siri on your wrist and Apple Music in your ears. It doesn't matter how much better google assistant or spotify is when they aren't available on the watch.
And going back to the main point, is Apple obligated to make other apps available as default options on your smartphone or smartwatch and if so, why? One can argue that more choice is always better, but I feel that at the end of the day, Apple built their own platform, and I don't think that Apple favouring their own apps and services necessarily makes them a monopoly in need of regulation.
This doesn't mean I won't welcome the ability to set overcast or spark as my default apps, but my point is that Apple doesn't, and shouldn't, have to do so if they don't feel so inclined.
If anything, it just goes to show the importance of controlling the key technologies underpinning your products. Owning Apple Music means that Apple is free to tinker with it as they wish and optimise it to run properly on their hardware and integrate with their services as necessary. Can you imagine if instead of acquiring Beats, Apple had entered into a partnership with Spotify to put music streaming on their Apple Watch, and spotify decided to play punk one day and hold back their service in order to demand for more money? Which is precisely what Google tried to do with Apple (which backfired when Apple refused to capitulate and introduced their own maps app). And the bigger and more successful Apple becomes, the more everyone else seems to want a piece of Apple, and the more control Apple will need to exert over its platform, if only to retain the strength it needs to stand up to any foe no matter how strong.
In the end, the safest hands are still your own.