Piping find -name to xargs results in filenames with spaces not being passed to the command

You can tell find and xargs to both use null terminators

find . -name "*.txt" -print0 | xargs -0 rm

or (simpler) use the built-in -delete action of find

find . -name "*.txt" -delete

or (thanks @kos)

find . -name "*.txt" -exec rm {} +

either of which should respect the system's ARG_MAX limit without the need for xargs.