2 is still more than 1, and there was a lot more competition in the intervening decades when there were more than 2. So it sounds like it worked for the most part? Certainly more so than doing nothing.
The issue is that the baby Bells were allowed to reconsolidate at all, or allowed to avoid competing in other provider's coverage areas. I agree some good came of the breakup, but the hands off position taken by subsequent administrations has allowed most of the Good to get undone.