There’s a difference between having a camera on your phone and having all of your services tied to one account. Once a picture is taken, you can do anything you want to it and there are any number of apps and services to help you do that. But if megaservice decides you violated some term of service, whether you actually did or not, you stand to lose everything – your email, calendar, wallet, messages, and access to any service that used megaservice for authentication.

Bundling things together is good when it reduces friction for the consumer, but bad when it reduces choice for the consumer. Every decision about bundling needs to be understood from that perspective, and evaluated on a case by case basis against that tradeoff.

That loss of choice is especially anti-consumer when a provider leverages a dominant market position in one product to push their own inferior version of a totally different product. For example, right now there’s a competition for consumer cloud storage. But none of the providers are actually competing on cloud storage features or pricing. All of them are competing based on bundling with the other totally unrelated products provided by that competitor:

• Apple pushes iCloud by giving it first party advantage on all Apple devices, with system and OS integration that the other cloud providers aren’t allowed to match.
• Google pushes Google Drive by using that storage space as part of the quota for Gmail, Google Photos, and Google Workspace.
• Microsoft pushes OneDrive as an add-on to its dominant position in Microsoft Office and Exchange, and gives it first party integration into Windows.
• Adobe pushes Adobe Cloud as an add-on to its dominant position in its suite of apps
• Amazon gives cloud storage to people who subscribe to, like, 2-day shipping and a TV streaming service and discounts at Whole Foods, in what is probably the most absurd bundle of them all.

And you see it everywhere. YouTube tries to protect its inferior Music service by bundling it with ad-free videos, Samsung put the inferior Bixby assistant on its phones, Google uses its dominance in browser, search, and maps to protect its advertising business, Apple gives its credit card preferential treatment in its payment app, etc.

So when a service protects its own affiliated service through unfair/preferential treatment, it harms the consumer by making the entire bundle less useful than a bunch of independent services, each competing to be the best at that one specific thing.

Hard disagree. There is a huge difference between the convenience of having a camera on you at all times and giving control of all of your services to a single provider or company that then locks you.

It’s not like the different apps make my phone take up more space in my pocket.

As far as I know, “a program should do one thing and do it well” is unique to the Unix philosophy. In mechanical engineering we have no comparable philosophy for components with weight; twice the moving parts cost twice as much.