For all the data to be stored locally is significant more engineering work. And most venture backed startups aren’t going to make that investment, as it’s unlikely to pay enough dividends to offset the engineering costs. So, they’ll scoop up all your data most likely
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keep an eye on https://opfn.co and https://argo.computer - you might be right, but these guys are trying it and may prove you wrong.
I would love nothing more than being wrong!