Yeah, you usage is pretty normal these days, for the reason you describe. You’re not the only one having to download 80GB updates or 150GB games off Steam, pretty common these days.
Here’s our usage for the past few months. Just changed to this ISP in December which is why that’s so low:
It did actually surprise me to learn how much we use. At the last ISP they didn’t tell you how much you used, so I never knew. When we switched to this ISP I thought something must be wrong 😆