But it is a huge waste of money for most coding tasks. Opus is still overkill most of the time, too.
It was working better than Opus for me. It more often implemented features well on the first try, where Opus needs a few rounds of improvements to reach a passable result.
I am not sure why it would be a waste of money "for most coding tasks", and how you could conclude so with any confidence when you did not even really use it aside from final review passes.
I can confidently say that Opus is the most powerful model I need 99% of the time. Fable might be marginally more capable than Opus for just about anything you might throw at it, but those gains aren't worth the cost for me.
The key is not to indiscriminately use the most powerful/expensive model you can for everything. When you use it for what it's uniquely suited for and ask it to spawn subagents using Opus and Sonnet based on what tasks need, you'll get better results at a reasonable cost.