I'm sure some of these other smart phones are great. My problem is since the late 80s I have used Apple Mac kit for graphic design and the software we used was not available for PC.
Nowadays my iPhone, iPad, MacBook and desktop computer all talk to each other - and to change to PC, which is so much cheaper, would still cost an arm, a leg and several other body parts...
Also, over the last 20/25 years I have heard so many tales of pc owners talking all weekend to install a new system and having to rebuild after virus and malware attacks that I would be largely against a complete change.
One thing about Apple kit is that it just seems to work - and I have never had a virus or been infected by malware. This peace of mind alone makes Apple the option for me.