Being stuck with MariaDB/MySQL in some projects, I recently compared it to PostgreSQL and found many of these extended capabilities existing there also, including JSON, temporal tables (w/ SYSTEM VERSIONING), columnar and vector storages etc.
LISTEN/NOTIFY type functionality was sort of missing but otherwise it was surprising how it is keeping up also, while little of that is probably being used by many legacy apps.
Interesting read, I was comparing some of these tools earlier for small web shop use while I didn't proceed to setup any of them just yet. Demoed Elastic, SigNoz and Grafana Loki, of which Alloy+Loki seemed to make most sense for my needs and didn't cause too much headache setting up on a tiny VM, so that I would have collection going in the first place and a decent method to grep through it.
Currently collecting just exception data from services to GlitchTip (Sentry fork), seems most valuable sysadmin-wise while having most security etc. concerns outsourced to managed hosting companies.
I didn't fully understand this idea of hydration but I also got recently interested in leveraging Wasm, in context of running parts of backend logic using it (eg. regular templating and some Htmx endpoints) to allow certain offline features with regular server-side web frameworks that could use similar Sqlite Wasm datastore as OP.
In last few years, surprisingly many parts of Python ecosystem to have gained Wasm support that can leverage this also. Obvious ML related ones and even game libraries like Pygame and Pyxels. Kivy support (multi-touch UI library) should not be too far out either now that SDL2 library has added support.
Seems like there's many new possibilities for running code in any computer, optionally sandboxed in web browser to avoid platform bureaucracy or taxes.
Coolify is quite nice, have been running some things with the v4 beta.
It reminds a bit of making web sites with a page builder. Easy to install and click around to get something running without thinking too much about it fairly quickly.
Problems are quite similar also, training wheels getting stuck in the woods more easily, hehe.