What does "AF AX p" mean in CTL?
Your understanding of $AF AX p$ is correct (in my opinion). But whether it seems particularly strange or hard to understand is rather subjective. The argument you quote compares the expressiveness or usability of LTL and CTL, and tries to convince readers that LTL is easier to understand (especially for engineers in practice). 

In my experience, it indeed takes more time for me to figure out and confirm the meaning of $AF\,AX\,p$ than that of $AX\,AF\,p$, which is in turn more than that of $X\,F\,p$ or $F\,X\,p$. By the way, if $AF\,AX\,p$ were easier to understand than the other three formulas, you  would probably not bother asking for confirmations here.