In almost all services this tends to get an asterisk that says "unless your usage interferes with other users" which in itself is poorly defined. But typically means once their system gets closer to its usage limit, you're the first to get booted off the service.

No ISP I've had in my adult life had such conditions, it truly is "Whatever you manage to do with the bandwidth we give you". I've done hundreds of TBs for months without any impact to my bandwidth (transferring ML datasets among other things), and I'm pretty sure a ISP in my country would break some law if they'd limit a typical broadband home connection based on data transfer quotas.