Translate the following English sentence to French:
"On the basis of the Commission' s proposal, we have unfortunately allowed ourselves to be persuaded to adopt old quotas which frankly promote cars made of steel rather than modern, versatile cars which are made of other materials and which are much lighter."
Le projet de la Commission nous a malheureusement amenés à opter pour d' anciens quotas qui favorisent une voiture en tôle et non pas la voiture en matériaux modernes à usages multiples, qui serait beaucoup plus légère.