They still provide stroke versions of icons in the newly released SF Symbols app. I wonder why they didn't go with adding only filled icons to help make the statement in your screenshot more solid.pic.twitter.com/Z6K8YmGw4o
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They still provide stroke versions of icons in the newly released SF Symbols app. I wonder why they didn't go with adding only filled icons to help make the statement in your screenshot more solid.pic.twitter.com/Z6K8YmGw4o
It's kind of a hollow statement, huh? 
I have a 3rd thing to say...Why is the "filled in gray" icon considered the inverse of the "blue line icon" in the incorrect example? Shouldn't that be a "gray line icon" instead? This example is so weird.
I had the same thought
Isn’t this just referring to coordinating icon weight? It says “if an icon must include lines” and “in general” How is this saying that it’s no longer acceptable to use line icons?
I think you're right. To me this is an example of an icon that *must* include lines (to properly illustrate the hands of a clock). The example shows how to coordinate the weight of the set. I don't think they're saying to *never* use light weight icons.
9to5mac is all I can see...
I agree, but I *think* the X and the checkmark would be considered symbols and not icons, since they’re conveying a state and are not a tap target 
It’s long been known that ghost buttons reduce legibility and should be used with care; it’s great that Apple (finally?) follows the empirical research that’s been done on this.
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