I believe I felt that one in Croatia. Started on 6-7th November.
My ISP Tele2, Croatia. But, I am on a 4G LTE router.
Haven't had it for 2 years since I've been with that ISP nothing the same as described.
Or at least we had some strange stuff for a few days, I thought it was my dedicated server SSH and MTU, bu not.
When connected through the VPN, the speed is normal, fine.
Also, FTP was working fine.
But, without a VPN, the network seems to be "throttled" somehow, do not know why.
Persists today. I have to use VPN for SSH connection to my server and to download on my "full speed" over FTP.
And my router is D-LINK, since firmware upgrade cannot access HTTPS configuration. Bad certificate :/