Those inventors who made eyedrops that can solve cataracts, why don't they produce them themselves ?
Those eyedrops that have been bought for billion dollars, those who made them could do them again, and could change little things tnat would make them different enough from the originals, so that they would not be protected anymore...
And if those persons are just scientists and not trained for business, why not start some project around their discoveries with the help of some contractors, with investors or/and collecting money through the net or using other ways...
II think that if such eyedrops would exist, or do exist, the project could be profitable enough to pay for expenses...Considering the number of people becoming blind from cataracts, there would be many demands for eyedrops that would heal them or prevent the issue...