I think it's constructive to tell them their site is broken (which I also agree that it is[1]). However, you are also right that your parent was unnecessarily condescending.

[1] There are billions of links which are just plain <a href="X"></a>, so the fraction of the ones that do something weird (like this, or target="_blank") really break the browsing experience for people.

Come on, the site is horribly broken in multiple obvious ways. No one gets a break for that.

I have to report that I tried to mess around with the AGL example and got a perpetual loading screen. The concept seems good; the execution, lacking.

Maybe this is not supposed to be public?