Plugin all the things!
I suggest as others have that most features could be plugins. I also suggest the plugin api needs more hooks. This could mean when looking to integrate features the maintainers use each opportunity to explore how the plugin api could be extended to accommodate the feature as a plugin.
Code Simplicity, an underrated classic, suggests that in each iteration you make the software no more complicated than it need be. Then as new features are added, you refactor to extensibility making it easy for the new feature to be hooked in. These principles are among the best in software development.
To summarize most new features should become an opportunity to extend and use the plugin api. Logseq may ship with a prerequisite set of plugins, but users can opt out. All the while the plugin api evolves for the better. If Zotero, a core feature I will most probably never use, were a plugin I’d drop it.
I give huge props to the creators/maintainers of Logseq. It is amazing FOSS.