To help you understand better, the industry already does offer the less effective insulins like Regular, Novolin and Novolin 70/30 at a reduced price. They aren't generic, but are less expensive because they've been replaced by something better.
The better insulins like Novolog and Humalog (start time is dramatically faster than Regular) and Lantus and Levemir (lasts longer and has less dramatic peak than Novolin) cost more. They won't offer generic prices on these until more effective insulins replace them.
I've been diabetic a long time and have used each of these insulins over the years. When I haven't had insurance I've been grateful for Regular and Novolin. But if you have insurance or are well off, the more expensive types really are worth the money.