edit: curious, how were these notices served to you when you were receiving them? Were they sent to the colo who forwarded them to you?

Anecdotally it seems the only enforcement in the US these days is via ISPs who have made some agreement to "self-enforce" against their residential customers, sending emails threatening to cancel service after three strikes. They seem to only monitor for select "blockbuster" level movies. A friend got one of these as recently as two years ago from CenturyLink iirc. Meanwhile I lived in an apartment building that had a shared (commercial) connection for all the tenants and eventually stopped using a VPN at all, never heard anything.