This is not true. There are email standards out there to help prevent spam. But right now Google simply ignores all this even if everything is setup correctly. I think Google has a responsibility in helping me debug _why_ an email is spam and give tools to fix it. Currently, there is 0 information, 0 support. The webmaster tools simply say everything is awesome and dandy. And you can't do anything else.
Here is today' world work flow:
1. Buy a domain
2. Have to use Google because your mail will end up in spam with any provider (unless it's outlook or some special provider).