Honestly, I would expect a big company like coinbase to have several backups of user data otherwise it's gonna be a tricky situation if shit happens.
And the bottomline is still cryptocurrencies are not insured. I guess they have taken steps in case shit happens but you could tell they're not confident about it.
This particular bit screams like the typical "we will do our best" to me which promises nothing in particular but provides a positive outlook nonetheless.
In case of a covered security event, we will endeavor to make you whole. However, total losses may exceed insurance recoveries so your funds may still be lost.