If you read the blog post, it goes over several good changes:

- What we’re changing

- Developer defense fund

- How we’re working to improve the law

Right; but the motivation looks rather like the attempt to restore the good reputation after an obvious mistake; one might have expected Github to check the DMCA request a priori and reject it if unfounded.

Even if so, that doesn't mean that these are not good changes.

Sure, better now than never. Let's hope it's not just a marketing campaign and that they are really serious about it.