incorrect SQL generated to summarize data

[dwhollick]

/* summarize sashelp.class with one row per age and a variable called "namelist" containing a comma delimited list of names */
Select Generate Code.

The generated DATA step works if sashelp.class is sorted by AGE:
data summarized_class;
set sashelp.class;
by age;

length namelist $200;
retain namelist;

if first.age then namelist = name;
else namelist = catx(',', namelist, name);

if last.age then output;
drop name;

run;

The generated SQL with does not create the same or desired output. The name do not get concatenated per age.
proc sql;
create table summary as
select age,
catx(", ", name) as namelist
from sashelp.class
group by age;
quit;

Also generates this log message:
WARNING: A GROUP BY clause has been transformed into an ORDER BY clause because neither the SELECT clause nor the optional HAVING
clause of the associated table-expression referenced a summary function.

Other incorrect SQL variations generated when I tweaked the comment language:

proc sql;
create table new_dataset as
select age,
catx(',', name_list) as namelist
from (select age,
catx(',', name) as name_list,
count(*) as count
from sashelp.class
group by age, name
having count > 0);
quit;

proc sql;
create table new_dataset as
select age,
catx(',', listagg(name, ',')) as namlist /* do not think listagg() is a SAS function *?
from sashelp.class
group by age;
quit;