> Aqua's color emphasized interactive elements using visual contrast.
There were loads of complaints about readability with Aqua, particularly of the menus and the windows title bars, both of which were translucent and had pinstripes. Briefly discussed here for example: https://arstechnica.com/gadgets/2011/05/mac-os-x-revisited/ . There was also the uproar at Leopard’s transparent menu bar and glossy dock, discussed here: https://arstechnica.com/gadgets/2007/10/mac-os-x-10-5/ . All these were over the top initially and were toned down and tweaked over time.
> How will those same audiences react when they see a glassy squircle pop up on their iPhone?
It’s a button. It has a shape, some physical character, and when you poke it wiggles and does something. It looks miles better than the label-button-links things that looked all identical in iOS 7 and that still plague modern design.
> This is objectively bad design. I would argue you don't know what made Platinum and Aqua great if you're comparing those complaints to this clown vomit.
I did not really like Platinum (I spent quite a lot of time with Kaleidoscope, which I miss very much). I really liked Aqua, though, despite its occasional brushed metal excesses. I would not mind going back to Lion, when they toned down the glossiness they introduced in Leopard. I think that UI was very elegant. But I have to admit there is a kind of playfulness with the concept of liquid UI that is intriguing. I love how the Dynamic Island reacts and behaves as it splits, grows, and shrink. I think I like it better than iOS 5-era glossy everything, and definitely more than iOS 7+. I am willing to admit that I have bad taste, but I am optimistic about the possibilities with the concepts they showed.
That said, I swear I read the clown vomit but about Aqua back in 2001. Some things never change.