For some a tiny phone screen is not a possibility. Also phone games are not equal to steam games. And some would not want to own a Steam Deck or Switch and pack it around with them in case they need to charge. It certainly isnt a priority, but if your car has a computer capable, why not?

Not seeing this in the US, but it is 2.99 on GOG and Humble store

Some Apple users regard this as a status symbol, some even excluding android users to avoid the green bubbles. This is probably because they perceive android as inferior since green text bubbles are associated with degraded performance largely imposed by apple when falling back to sms for interoperability (crappy pic quality, spammy notifications). Apple uses this to help keep iphone dominance (at least in the US).