I've lived/live in both worlds. Was early DOS/Windows guy, became
an Apple evangelist in the 90's, early 2000s, but over time saw Apple
become something other than what was Steve Jobs's vision. Was
even able, as an IT Manager, to get some Apple products into an
IBM/Dell-only telecom.
It is now, simply a "walled garden" company returning to "not invented
here" mentality. Don't get me wrong, Apple makes fantastic products.
I no longer use iPhones. I can't see myself ever returning to the fold.
iMacs, MacBooks, yeah, macOS is awesome. 'Nuff said. Tho I worry
Apple's trajectory is becoming more and more closed as the years
go by.
As for AV, I've usually not had to use any on Android. It was on by
default on my new Galaxy S21 (which is a pretty amazing phone),
and I've left it on, though I probably wouldn't have an issue turning
off. @huZZah is right, it's no longer true that Apple is "immune"
(by quantity) to viruses/malware. As the rest have said, avoid "bad"
places, and don't click on links in emails w/o being absolutely certain
they're legit.