Hmm you're right. I could almost swear this trick has worked for me in the past, either I'm wrong or something has changed. The only way, then, is to use the -a switch and write an alias that does the sorting:
alias tldsort if ($gettok($1,-1,46) > $gettok($2,-1,46)) return 1 | return -1
Then use
/filter -c
aio dname id dname id
tldsort
