Those fleet lessors are not the manufacturers. If the lessor goes belly-up, you can lease the exact same model of plane/train/etc from one of their competitors

Those fleet lessors are not the manufacturers. If the lessor goes belly-up, you can lease the exact same model of plane/train/etc from one of their competitors.= If Boeing's financial stability depended on the sucess of one particular aircraft lessor, that would be a huge problem.