Fine, but you are still assuming that other people's preference are likely to match your own
If I assume anything, it's that the vast majority of users are ignorant of the choices they have.
I'd say that's a pretty safe assumption.

I make no assumptions about their particular preferences beyond matters which effect my own sites and which are likely to contradict my own ideals for those sites.

On the off-chance that users are more-likely than not to have no clear preference, I offer them the choice.
In the absence of them choosing an option, I set the default option to match my own.
How is that an "arrogant" position?
I don't see how I can be fairer than that - do you?

I maintain that, in the absence of a clear user's opinion, it should be perfectly acceptible for the author to present their site(s) according to their own presentational ideals.
I make it clear what they can expect. If they don't share my views on how certain 'negotiable' aspects of my site should be handled, then they are free to switch the option to whichever they prefer.

There is no greater consideration you can offer to uninformed users than to inform them of the choices they have.
Given that I offer a clear, adaptable choice, what preference is it that I'm allegedly arrogantly inflicting upon my users?
If I'm inflicting anything upon them, it's the option to have an opinion. If that is too demanding, then, to be honest, they are more than welcome to leave my site as their presence at said site is unlikely to enrich and benefit either of our lives.

As it stands I'm not savaging my users and I haven't advocated such a position.
How would you suggest that I could better reconcile my own preferences for my site with the choices its users?


Or is it that you, as a web-designer/developer, believe that site authors shouldn't be allowed to have their own opinion as to how their site is ideally delivered? (honest question)

I will never subscribe to the notion that the views of a site's authors are the least important.
I will also never shy away from pointing out that the vast majority of users are pig-ignorant when it comes to browser choices and browser features (so long as it remains true).

fwiw, unexpected popups pi** me off too, especially fullscreen ones.
A full-screen, unannounced popup will very often be enough to have me closing their window and going elsewhere.

Anyway, I think we're both clear where we stand.