No, that is not the trend. A lot of things that perform multiple duties in Perl 5 will receive separate names in Perl 6 (the two forms of for, the two functions called select, and many other things besides).

I don’t see any reason to go counter to this trend by conflating join and reduce. List::Util has been in core for a while so is more likely to be available than this proposed extension of join, and “join” is a bad name for a reduce function anyway.

Makeshifts last the longest.