Wanting to keep humanity IN AI is survival, quite a common human value.
That's long-term species survival, which is not an overriding one, nor is it a universal one. We're more likely to stop fighting wars and using fossil fuels long before we embrace AI and/or brain uploading on their own merits.
On the other hand, "survival" in human terms is individualistic. When you wake up one morning with an empty stomach and an empty fridge, the first thing most people think is "I better go find something to eat," not "I better go program a smart AI that can increase global food production enough that I'll have more to eat in the mornings."
Smartphones are basically a buffer to your brain already
No, smartphones are handheld computers that double as communications devices. They're no more a "buffer to your brain" than a pencil and a post-it note, except that while everyone in America knows how to use a pencil, not everyone knows how to use a smart phone, or even owns one.
You also continue to ignore the fact that implanting a chip in your brain involves a highly invasive major medical procedure. Most people -- NORMAL people -- would probably elect not to undergo major brain surgery unless it was medically necessary; putting a smartphone in your brain isn't medically necessary, especially since that same smartphone fits just as handily in your front pocket.