This has driven my interest into Roam... a freeform ability to connect sources/idea/data that can drive cumulative value over time rather than fragmentation and dusty old drives/notes.
I used to use DayOne as a journaling program until I realized the same thing: as soon as I stop paying, all those memories are gone, lost in time like tears in rain. Sure it is really nice and convenient software and the user experience is fantastic but if I stop paying, it's all lost. If they raise their price higher than I want to pay, it's all lost. If they go out of business or pivot or get sold or... it's all lost.
I'm willing to take that risk... but I'm not willing to pay for the pleasure of taking that risk. I ended up just writing everything in Apple Notes that's free on all my devices. Sure it's the same risk, but at least I'm not paying $165/year for something that can disappear whenever the founder gets bored.
Yes, this is why I made Open Source and open formats an absolute requirement when I started looking at journaling software. The content is irreplaceable.
After trying several things, I found that Joplin does everything that I need for journaling and note-taking. I made a point of donating to the project the equivalent of what I would have paid for a commercial offering.