Are some O365 MDM features available even before setting it up?

I have not yet activated O365's MDM as can be seen here:

Nonetheless, the ability to set password policy, etc. here:

seems to still be available.

Is this feature set something different than MDM or are some MDM features avaialble even prior to setting it up?

Solution

Configuring a policy doesn't mean that MDM has been applied, you still need to apply MDM at the end, if you need the policy to be functioning.

you can go to the Security & Compliance Center, go to Security policies > Device security policies; check if the policy is on or turned off.