> I really never understood how people could store very important information in ES like it was a database.

I agree.

Its been a while since I touched it, but as far as I can remember ES has never pretended to be your primary store of information. It was mostly juniors that reached for it for transaction processing, and I had to disabuse them of the notion that it was fit for purpose there.

ES is for building a searchable replica of your data. Every ES deployment I made or consulted sourced its data from some other durable store, and the only thing that wrote to it were replication processes or backfills.