I don't think a mega corp having full access to my phone while me not having that is very "secure". Sure it's pretty ok against third parties but in my threat model Google and Apple are also adversaries. Microsoft too by the way.
In my model my Linux pc is a lot more secure as there's no adversary having direct access and more control than me.
That makes no sense. Equality is commutative and security is most certainly not privacy. There are certain areas where a decision may help in case of both (e.g. simply not storing unnecessary data will decrease the scope of a real vulnerability), but that's not even remotely the same thing.
By this definition no operating system Google releases will be secure to you. I think it would be a more productive discussion if you could argue about security ignoring that you have to trust the person who wrote your operating system or designed your cpu.
I think their point is that the source being open keeps the developers more honest. Of course there have been supply chain attacks in open source, but that is more probable to be found out than closed source ones. In short, auditability improves security.
It works well for you.. but for average person. No.
As a 20 year old linux user, I do often use ChromeOS or ChromeOSflex. Just works. Beautiful UI. No more pain with webcam or wifi drivers - Yes, these have improved by still one has the pain of dropped packets (realtek wifi) etc. guaranteed 10 hour battery life.
With ChromeOS I just get 4 or 5 second - update - immutable OS. Fedora Silverblue is coming up but still not there.
That's not the relevant part. The relevant part is, if you find it's doing something you don't want it to be doing, can you read and modify the code that does that?
In my model my Linux pc is a lot more secure as there's no adversary having direct access and more control than me.