The rejecting of climate change is pretty easy to account for. A lot of people use climate change to push whatever their personal agenda is:
The climate is changing so we need to...
Instead of debating all the kooky non-sequitur solutions are being proposed in the name of climate change, it's easier to just throw the ball back in their court by questioning whether the climate is even changing at all. If debating an actual climate scientist, this might not work very well, but when confronted by people who know little about science and are just using it to lend urgency to their pet cause, this is effective at shutting down their rant about how we must do such-and-such in the name of global warming.
People do this sort of thing in other areas as well. For instance, when faced with someone proselytizing religion, an agnostic might not want to get into some long discussion about what concepts of the divine they are and are not open to considering, and instead just say they don't believe in God at all, even if their private views on spirituality happen to be more nuanced.
Sometimes people take a hard line position just to shut up people they don't want to deal with.
Having no headphone jack (which I use every day) makes this a downgrade not just from my existing phone, but from the first-gen iPhone I had over a decade ago. Sure, you could use a dongle, but why?
The lack of a Bixby button is lame too. Bixby itself is useless, but having a remappable physical button is very handy. I use the one on my Note 8 to turn the flashlight on and off, much quicker and more convenient than doing it through the GUI.
Every nonzero finite dimensional inner product space has an orthonormal basis. It makes sense, when you don't think about it.