85 TB/year to run a full node is too high? What am I missing?

Had a conversation with a crypto friend today about running a full node between ethereum and bitcoin, and he mentioned that, in one of the banklessinterview, u\vbuterin says something like ethereum blockchain data is 2.6 megabytes/second, which is 85tb/year. Vitalik then said, "if you have one person that just keeps buying $100 hard drive once every month, then they can store it. It's too big for a casual user, but one dedicated user who care can totally afford it and store the chain". Now, my friend is arguing that this is the clear sign that eth is centralized, since you can't expect normal ppl to just spend $100 every month, considering you don't earn any money for running a full node. My argument back is that this is only the cost of running 1 full node, and we technically don't need everyone to run full node, we only need person to do so to make sure no data is completely lost. Is that the right way to understand it? what am i missing?