I mean it will work, but for a blog I'd store the pages in markdown files, to make it easier to edit. For context, look into how Hugo works

A few circumstances to consider...

If it's just your own little tool and you don't intend to share it with others: do whatever you want. SQL or NoSQL or JSON, it doesn't matter. Use your own judgement.

In my experience tho most homegrown JSON-based "databases" tend to load all data into the memory, simply because they are very simplistic (serialize everything into JSON and write to disk, deserialize everything into a struct). If your dataset is too big for that, just go straight for a full-fledged database.

TinyDB literally does this. in general its more of does this work for my use case and am i aware of its limitations.

If it works then it works.

yep, though IO might bottleneck you at some point, and then you can happily switch to mongoDB