For the most part, yes I believe the blocking is for malware sites. The current list I am aware: malware sites, deceptive sites, suspicious sites, sites with possible harmful programs, sites that load scripts from unauthenticated sources, sites that chrome believes were typed incorrectly.
I didn't intend to imply that chrome currently, intentionally blocks sites on other criteria. However, the framework is already there.
History shows that the ego of people always takes over if left unchecked. When it is possible to restrict something, that will eventually get restricted. This is especially true when discussing large companies, such as Google.
I was agreeing with you and not correcting you :-)