The difference between Chrome and Safari not supporting features is that Safari is developed by one company (Apple) whereas Chrome is developed by two (Directly by Google and indirectly by Microsoft). So Apple can have an incentive not to add a feature and end up harming the entire industry. But if Google has an incentive not to add something, Microsoft can still add that thing anyway (and vice versa), we only need one actor to act good for their not to be harm caused.
> 1. [...] A tiny number of developers who don’t already have access to an Apple device have to spend literally tens of dollars buying or inheriting 5+ year-old devices in order to test on a diversity of platforms.
This is flat out wrong.
One Safari is not equal to another.
You need to buy one of each device because Safari will change how it works across different devices.
Example 1: Safari adds depth touch to some devices which adds weird box overlays around parts of the website while the user is trying to use it, which blocks the content and interferes with which elements are supposed to be interactable unless you add special webkit-prefixed rules (e.g. -webkit-touch-callout, -webkit-tap-highlight-color, etc...) to different parts of your pages.
Example 2: Safari adds different buffer areas around their browser which you need to test with (using the env() css function) on each device with a different screen to make sure content isn't flowing off the screen or elements are being cut off at incorrect spots when they're supposed to flow past the edge.
And so on...
Apple keeps adding device specific ways of breaking websites.
Furthermore, each device can only run one version of Safari. Every time a new version comes out, you need to upgrade your OS to get the new version of Safari. And you also can't downgrade your OS to get the older version. And because some users can't upgrade and others won't, you need multiple of each device running each one on a different version of the OS to test correctly.
We have to spend 1000s of dollars each year on new devices just because Apple keeps inventing new ways of breaking things.
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Side question: But what about just buying a mac and running the iOS Simulator to test different versions of Safari on different devices?
It's no good, the iOS Simulator is a simulator, not an emulator. So the bugs that are on the device are not the same as the ones in the simulator.
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So out of your two options, what will happen is:
Some users will switch to Blink/Chromium and find that things start working better. That will start to build up a reputation of Chrome/Edge/etc... working better than Safari.
Meaning Apple will need to invest more money and effort into improving Safari.
Meaning Safari will be improved.
So either users start migrating to a better browser, or Safari improves to the point that it isn't a problem anymore.