It is not catastrophic, but there is an increase in the junk mail getting through.
A: Because gmail, yahoo and aol have managed to get their servers listed in Uniform Resource Identifier Blacklist (URIBL) databases. **
The Q/A above leads to the P/S below (as distasteful as it may be).
Problem: gmail (google), yahoo and aol [and others] are URIBL blocked by the spam filters/servers, we all want email from our friends at gmail, yahoo and (yes, still) aol.
Solution: turn off URIBL blocking at the spam filters/servers. (Throw IN the bad bathwater with the good?)
Someday, maybe, the internet will be a better more friendly place to live. Until then, a few more *Junk* emails every day.
** gmail, yahoo and aol do not provide ‘easy platforms’ for spammers, phishers and junk/bulk email proliferators; they get listed on these ‘block lists’ by their competitors, odd-balls that hate big companies and goofy, immature people that have nothing better to do.