You're starting from the perspective that these restrictions are warranted.

High performance browsers never could have been written in the first place if PCs had these restrictions in the '90s through mid 2000s.

Who knows what "application of the future" will not be viable on iOS etc. because they're afraid of writable executable pages or any other undue restrictions.

I don’t think they’re warranted at all technically. It would just be a lot of work for Apple to now allow new browser engines with no clear benefit to Apple.

I do believe what I am saying about security is true, and it would be a non-trivial cost for Apple to have to start worrying about what happens if Chromium ships with a security bug, but at Apple scale it’s less about that cost and more about the complexity it introduces for no benefit to Apple.

To clarify I am not saying Apple’s decision is good. I think it’s very bad. I am just trying to see it from their perspective, and have to admit, it makes complete sense

And those high performance browsers also do things that if Apple allowed could result in security vulnerabilities. Even Apple disables those capabilities in its own browser in the new high security mode.

Besides, you can say a lot of things about Firefox and Chrome - but high performance and memory and power efficient aren’t traits you assign to Chrome.

PC's also had an unending stream of viruses. I don't want to have to deal with exploits on my phone.

And from a technical standpoint, high performance browsers enabled the world to misuse HTML + JS to create applications, instead of being limited to documents like it was designed to do. As a developer, building native applications is a lot more fun trying to coerce the browser into doing what I want, because the underlying design actually does what you need it to. Unless "native" means "Windows", though, that has always been painful unless you use something like Qt.

> PC's also had an unending stream of viruses

Back in the 1990s,, when I used them, Macs had an "unending stream of viruses" too. DO they not these days? Does windoews still?

> PC's also had an unending stream of viruses. I don't want to have to deal with exploits on my phone.

This is a false choice. How many of those viruses existed because you could, as a concept (not as a default), mark a page as executable at runtime? I'm going to say precisely none of them.

Android has whichever browser you want, doesn't have an unending stream of viruses, and even allows for piracy through side-loading of apps ... so this is not a necessary measure.

> It’s not clear what they gain from allowing other engines

Apple gain nothing. That precisely why they don't do it. However, we all suffer from a web platform that gets held back by there being zero competition on iOS.

I guess what I’m saying is that unless legislation or a court make Apple support other browsers, expect nothing. Apple won’t acquiesce just because technical users and developers don’t like having to use WebKit.

Despite it being a terrible decision, I don’t think it affects Apple’s bottom line positively at all to support other browser engines: they won’t make any money off it, will create headaches for themselves since they need to expand their security surface and do some technical work to support it, and cede control to competitors. Approximately nobody (weighted by financial impact to Apple - whether Firefox uses WebKit or not is, as far as I can tell, completely irrelevant to Apple’s bottom line) is deciding not to release on iOS because of WebKit.

I'd wonder if EU antitrust laws could give them something to gain: namely, not being fined. There's a concept of market fairness in EU antitrust law that isn't present in the equivalent US rules, such that price is not the only consideration.

I'd be surprised if this couldn't be turned towards pushing for greater user choice as it was when MS was bundling internet explorer for years. If memory serves, it was competition law which was used to undo that.

They risk losing market share if another unsupported browser is seen as sufficiently superior that users avoid choosing Apple products on that basis. I don't even mind Safari, but I'm still in no hurry to lock myself into the iPhone ecosystem, partly due to those sorts of restrictions.

Other browsers are allowed, just not other browser engines. The reasons for this are technical, not arbitrary or business related. Google, Firefox, Brave et al still get the market advantages of having iOS users on their platforms, and they can and do ship their own unique browser interface features. That should count as competition.

I strongly disagree. The browser engine is hugely important. It took Apple years and years to implement features like WebGL and WebRTC, those simply cannot be grafted onto an existing engine by a wrapper app. Without any meaningful competition Apple were happy to sit on those features and implement at their own leisure. That isn't real competition.

Another example: earlier this year it was revealed that Safari had a huge security hole in its IndexedDB implementation:

https://safarileaks.com

There's absolutely nothing that a web browser maker could do about it. They fall victim to the exact same bugs that Safari does because they have to way to avoid it. Again, not real competition. They also broke localStorage in iOS 14.1 and took three months to fix it. Because there's nothing forcing their hand.

> The reasons for this are technical, not arbitrary or business related.

Oh my sweet summer child. Apple has many business incentives to push native solutions over web-based ones. We'll never know exactly what motivates them or why but to totally dismiss any business incentives at work here seems naive.

Imagine Microsoft making that argument back in 2000...

I consider the browser Safari the bigger security risk because of the delay of security updates. They push security updates together with OS updates very unfrequently. Firefox, Chromium etc. push out security updates much more frequently. Would feel much safer on more regular smaller security updates on every security bug.

Not only that, but it means that a vulnerability in webkit or Safari impacts all iOS users. It's a gift to attackers.

If it lowers their attack surface does it not by definition increase security? Personally I want a full fledged firefox on my iPhone, however I'm not going to act like it makes iOS more secure.