The speed of light through optical fiber is slower than the speed of electromagnetic waves through air, so good wireless could be lower latency than good fiber.
Yes, but for whatever reason, no wireless connection is as good as a wired connection today, and as far as I know, wired will still be superior to wireless for a long time.
With 5G, the 'air latency' will be about 8-12ms. That is about the same as a wired connection (from your house to the ISP) https://en.wikipedia.org/wiki/5G
That will be nice, but I’ll believe it when I see it. Tech claims are usually exaggerated, or ignore overhead in the real world.