I agree "the new IE6" is a tad much, but this...

> there are a growing number of areas where Chrome and Firefox have nearly identical behavior and Safari is the odd one out.

...is definitely true for me when developing relatively simple sites. I develop in Firefox and it's been a long time since I've had to change any CSS to make it work in Chrome. Meanwhile Safari has had broken default SVG sizing for years now (unless they fixed it recently), ignores padding on <select> (so you need to set the height) and other things like that.

It's all minor, but it's annoying to deal with. Especially considering you need Apple hardware to test with.

But I can't complain too much, since I also still need to support IE11.