I'm not suggesting anyone gets a recurring subscription at all. You can buy the most dogshit pc or even something like an off brand raspberry pi and a $10 microsd card with hundreds of gigabytes of storage and have a permanent data backup solution. You can even skip the device if you're really struggling. Microsd cards are dirt cheap.
Combine that with grabbing several free tiers of data storage like Google, Proton, mega, filen, etc, you can rack up hundreds of gigabytes of storage, each with its own account so if one goes down or you lose access you can have the same data on the others. This can be for maximum priority data but even for low priority you can fit a lot of data on 15gb if it's not all high quality photos and videos.
And if I can reach a bit, even a 2nd phone is viable. Many phones are under $100 and they, at the bare minimum, "work" so one such phone can be kept as a backup.
There are many, many ways to have a very cheap backup plan. It's more about logistics than storage, and only requires a little bit of thinking and planning.
I was once in a place where I couldn't afford an extra $2 a month, like you mentioned. But I ALWAYS had a backup plan, and sometimes it was completely free.