How Prolog became an education nightmare (Was: 50 Years of Prolog Nonsense)

Concerning the input (xxx yyy zzz) the OP wrote:
I would expect it to print zzz(xxx(yyy)).
Where did he get this requirement from, he didn’t
compare other Prolog systems, right? So it came from
his applicationdomain. But what was his application
domain? Ok, lets proceed to an example with multiple
brakets. Lets make the Pascal “begin” “end” example,
by replacing xxx and zzz by “begin” and “end”.
I get this result:
?- member(X,[begin,end]), current_op(Y,Z,X).
X = (begin), Y = 1100, Z = fy ;
X = (end), Y = 1100, Z = yf.
?- X = (begin
|          x = 1;
|          y = 2;
|          begin
|               z = 3
|          end
|       end).
X = (begin x=1;y=2;begin z=3 end end).
But is the abstract parse term, the Prolog result useful?