I don't find Google blocks too well
Still using a Gmail account like an idiot, I do get spam through to the inbox on occasion.
Like this Tesco email, the entire content is an image with zero text. And Gmail does not let you filter messages that are just an image (nor am I sure I would always want to). With no words in the body, it is difficult to filter at all, as the senders change every time.
More research, more action welcome.