[abat]

Are they trying to deter non-serious students in order to inflate their pass rate?

If they want people to take their certificates seriously, I guess it would be important for people to trust that the person listed actually earned it. The documentation may also improve later conversion to paid products as well avoid the same person passing the course multiple times with multiple AWS accounts to get more AWS credit.

[wodenokoto]

No, this is for verified certificates. You can audit (and get graded) for free anonymously.