Internet is (increasingly: was) an open system that you can connect to on your own terms. Browsers do your bidding, for the most part anyway and you can switch if you don't like one of them. However, you can't simply install an open source version of Google Play Services on your phone and if the Deutsche Bahn app doesn't work for you, there is no alternative that you can install to talk to their server and buy that train ticket (no equivalent to installing a different browser aka 'user agent')
It was actually very easy to get by without any of it until quite recently, when legacy options for all kinds of things began being phased out.
But let's use 10 years: you absolutely could get by without internet 10 years ago. It would have been a bit of a hassle for a few things, but internet access wasn't needed for lots of every-day basic activities like parking a car, ordering in a restaurant, using tickets at a concert, etc.
Also: it was easy to use internet at a library, often at zero to no costs. You didn't need to have a personal device only used by you.