Eh. It doesn't seem particularly relevant to bring up Linux, with its hundreds of thousands of person-hours worth of volunteer contributions and an extremely technically focused BDFL gatekeeper.
It's a relatively well known fact that multi-team corporate projects have tech debt. There was a thread recently about Google Cloud being slow due to too-many-cooks-in-the-kitchen syndrome, and many ex-amazon folks say AWS UI is notoriously difficult to refactor for similar reasons.
I mean, Uber has had a huge number of people working on it too, with the incentive that they are paid to do a good job. Regardless of the eventual outcome, I have no misconceptions that Uber doesn't have some engineers who are extraordinary talented. And, the project is newer, too, with fewer guarantees on stability and fewer users to boot. I think it's a valid comparison to make at least–they are both huge, complex projects with a massive number of people working on them. Tech debt is inevitable, but I still think it is valid to call it out when it occurs and not try to excuse it with "but our app is super complicated, you can't possibly understand how complicated it is".
To be clear, I do think you have a valid point about e.g. unused assets and loading big libs to do trivial things, but IMHO, that's really a commentary on software development at large, rather than anything specific to Uber.
And there are cases, even in the Uber app, where thought has been put into optimizing both for upfront download size and internal complexity (the legal pages, for example)
Something that is worth considering is that a lot of what was said about the app being complicated is that it is also _dynamically_ complicated. For example, in the driver app, a feature was added to ensure drivers are wearing face coverings. The backend for that does AI-based fraud detection to prevent shenanigans like photos of photos. The picture upload flow is just one small part of a much more complex project that had to be rushed out because the covid pandemic happened. There are a bunch of similarly large impact things that touch several of the Uber apps simultaneously, often in non trivial ways and with tight timelines (e.g. features for compliance with specific legal requirements)
The reason I think Linux seems like a bad comparison is that if Linux contributors don't want to support some random driver for 3 years, that might be annoying but is generally just the way it is. Uber can't really afford to not do some of the complicated things it does in a timely manner.
What I don't really understand is why so much of the dynamic content ends up being native code on the client. For example, let's say you need to have some of legal compliance page. But there is always changes you have to make in a bunch of regions, and the flow is constantly changing, or whatever. But why can't this be a DSL you download and deserialize into views? Why does there have to be a hundred different native views for this that all must be part of the app? I'm hearing all these tail-end cases that one region hits and interacts with for seconds and I guess I don't really understand why these things are not handled server-side, making the app a dumb client. After all, isn't that how the website surely works?
I understand that Linux doesn't necessarily always have the product marketing deadlines or whatnot that Uber might have, but it's saddled with legacy code too. When things have security issues, or the API is just awful, at some point someone needs to fix it. Especially if your business is being decimated by a bug or you are lacking in APIs that meet your usecase. I don't think it's as poor as a comparison as you might thing it is.
I think a lot of it is driven by dysfunction and legacy at Apple. Their whole mindset is they want to review every version of the app manually and every bit of code that executes must be signed. They don't allow a lot of obvious software engineering approaches as a consequence, like partially downloading the app and streaming the rest on demand even though it's an obvious thing to do for mobile apps.
Note how in this story the Android and iOS teams started a big rewrite at the same time, but the story consists exclusively of fuckups on the Apple size. Apple impose an arbitrary cellular download limit. Apple designed a language that can't handle more than 9 dynamic libraries before it hits scaling issues. Apple prevent you from using interpreters or other techniques to change the app after it's installed, unless you use a WebView in which case it's OK for mysterious reasons. Apple don't help even when major brands are weeks away from wrecking their business by hitting these limits. Apple Apple Apple. Meanwhile the Android guys are sitting pretty with Java and now a migration to Kotlin, which is (a) a much better language than Swift and (b) is dogfooded at large scale on the IntelliJ project so you know it scales (had no scaling problems with Kotlin and I've been using it for the last five years).
I think the argument is more that even if you were to magically get rid of the cruft introduced by institutional bloat, the app will still necessarily be large given the nature of the business. Uber isn't some outlier here either; Lyft, Ola, Yandex, GoJek, Grab, etc etc all have comparable iOS app sizes.
It sounds stupid, but I'm going to say that they're all doing it wrong. One commenter in this thread brought up the Uber app for Android and it's a fraction of the size–clearly, market constraints can make it possible to do better?
It's a relatively well known fact that multi-team corporate projects have tech debt. There was a thread recently about Google Cloud being slow due to too-many-cooks-in-the-kitchen syndrome, and many ex-amazon folks say AWS UI is notoriously difficult to refactor for similar reasons.