Very annoying that you can't use an old Lisa development system like the ones Apple required for the original Macintosh.

I was traumatized a few weeks ago when my parents sent me a particularly jarring video of their Windows computer with audio playing telling them to call a number to get rid of something nefarious-sounding but quickly Googled it and realized it was a bunch of popup browser pop ups pretending to be worse than they were. I don’t run into stuff like that when using Firefox on my MacBook.

I think it matters a lot what you consider "Secure" to mean. Most security people are focused on stopping an attacker from remotely installing and executing malicious code on your device. Huge amount of effort is dedicated by security people to adding hardware to stop buffer over runs, make memory protected, signing code and so on, to stop these types of attacks. A more locked down system like iOS/Android is at least in theory more secure then a device ruining Windows and especially Linux, that lets the user install and run what ever they want.

If you on the other hand define security as in control over your device and your data, then the Mobile devices are terrible. A lot of apps are full of "telemetry" (read spyware) that in practice makes most Mobile device leaks a huge amount of data. You have very little control over this. This is an attack vector that is mostly ignored by these companies, because they dont see it as an attack vector, but rather as a revenue stream.