@gmail.com and @outlook.com are like 90% of the spam I receive. What’s missing is effective accountability for those two companies hosting persistent spam groups who operate for months unimpeded.
So wait, it seems like you're claiming that you're receiving spam from the same gmail/outlook address for months.
This is fascinating and I have a hard time believing it, might you be able to share some headers?
OTOH, if the spammers are forced to frequently switch accounts, they're clearly being impeded.