The weapon in question, the M20 recoilless rifle, turned out to be ineffective against tanks (even against T-34s which by the 1950s were obsolete), but effective as close infantry support against stationary targets. So it could still have been used effectively against e.g. Vietnamese or Algerian positions.
Looks like it was used in Algeria, actually, according to this source:
"La Vespa 150 TAP o "Vespa Bazooka" como la llamaban algunos tuvo su bautismo de fuego durante la guerra de Argelia (1954-62), en que varios cientos de estas motos fueron desplegadas y utilizadas por las TAP y la Legión Extranjera." [1]
Googla translation:
"The Vespa 150 TAP or "Vespa Bazooka" as some called it had its baptism of fire during the Algerian war (1954-62), in which several hundred of these motorcycles were deployed and used by the TAP and the Foreign Legion."
Curiously the Wikipedia page in French mentions Algeria as well, but has no sources, and the official military archives have zero relevant mentions of Vespa, M20, scooter, bazooka, ACMA.
