If you don't use video then it'll be plenty. Plenty of people get their TV the old-fashioned way but still want fast Internet.

Looking at pricing for Spark (one of the largerproviders). [1]

For each of the fibre speed plans you can get 60GB/month, for another $10 you get 120GB/month and for a further $10 you get unlimited traffic.

BTW: "Mb" = Megabits, "MB" = MegaBytes

[1] https://www.spark.co.nz/shop/internet/plans-and-pricing/

I mean, the video games I play are 100-200gb each, with crazy large updates every couple days. I would probably go through 120gb in a couple days.

Easily. Between updates and video downloads I expect to use about 200GB today alone.