I've been on various foreign carriers that seem to have the rule, but some of these same carriers don't enforce rules about stuff going under the seat in front. In particular, foreign carriers tend not to notice people storing things under their knees and behind their lower legs throughout flight, including for takeoffs and landings. IME USA legacy carriers are good about enforcing this prohibition, but do allow stuff under the seat. Also IME USA legacy carriers are stricter about the underseat stuff needing to be fully under the seat in ext rows.