If you’re just building a standard body scroll website with a simple ui/ux you’ll likely be ok. As soon as you start doing complex stuff with pinned panels, or gestures, animations, drag and drop then you’ll hit the bugs.
Some of the bugs developers have been complaining about for 7 years.
Every browser we develop has bugs, Safari just has 10x as many.
Multiple times I've hit issues with things that I would have expected to be 100% complete, like SVGs not being able to properly transition animations in certain cases.
- CSS outline not being affected by the border-radius property.
- Drag images being completely screwed up if the dragged element, or any of its ancestor, has a CSS transform.
Both of these problems have workarounds (insanely ugly hacks would be a better term), but they shouldn't have.
- Regular expression lookbehind
- overscroll-behavior
- Web push
- SVG favicon
- Web Bluetooth (haven't run into this personally, but someone complained about this)
- Nice to have - Problem - Don’t want it, will never allow it - Nice to have - Don’t want it, will never allow it
Of the five items you list, I only see one as a real problem. Two of them are privacy misfeatures that have no business being on the web platform. The other two are annoying and would be better to have than not.
For example, taking web push notifications, you and many others may not want it, but someone else and many others too may want it for whatever reason:
- maybe from a developer perspective because they're a hobbyist and don't want to create an app instead of a website just to get notifications, but would be happy if they had the option. And before you say you don't need them, you DON'T know their use case, e.g., if it's a chat web-app it's going to be pretty damn useless without notifications.
- maybe from a user's perspective because they're not happy granting additional permissions (or making it harder to use an ad-blocker) that could be required by an app from the store, they just need the push notification to get some alert, but don't want to give up access to their photos, files, or contacts too.
In any case, it's about having empathy towards allowing others to have wants/needs different from yours, and if you do that and put yourself in other people's shoes, you should be able to see that Safari is clearly lacking in implementing a bunch of features (or delivering them several years after every other browser).
Finally, all that doesn't take away the fact that Safari does some things better than others, and that other browsers do things worse or push features that are in line with their own agenda or monetisation strategy.
Safari is the modern IE in this respect.