Reporting to ICO is very straightforward and takes 2 minutes. I have a script saved on Notepad to copy and paste into each report, basically saying these are unwanted, annoying emails and they are affecting my mental health. You just copy the email address from where it was sent if you have it and tick a few more boxes. Maybe the more that do it, the more chance of someone taking it seriously.
I have had emails constantly over last few months, from different email addresses, but with RoodyNews or RoddyNews detailed at the bottom of the email, usually gambling emails, but now advertising Lemon Loans & British Seniors Insurance Agency. These both appear to be bona fide companies and both show an FCA number. So, I have forwarded the emails to them respectively and made an official complaint to them as if they weren't in some way paying RoodyNews then RoodyNews would not waste their time sending them. As far as I aware financial organisations can not send unsolicited email. They will have to provide info as to where they got my email address from otherwise I'll request a SAR from them and take up their time. I know it is a pain but I'm on a mission, even a crusade!! I read somewhere about a guy who sued a certain company in the small claims court and won. I don't want money I just want the emails to stop. My 'you know what' is big enough, there aren't girls within 5 minutes of me dying to meet me and no, I won't help the FBI or a Nigerian prince launder $900,000,000,000.00 !!!!
Seriously though, the more that report it the more chance something will be done.
A simple thing Microsoft could put in place would be to enable any user to set a rule not allowing anything that isn't from a .com or .co.uk domain to be sent to their email, junk folder or not. But obviously there is a reason for that and it will obviously be financial.