I’m still on the fence myself. I used to have Espanso running but I didn’t use it often enough. I used to have the templates plugin on but not anymore.
I made a small proof-of-concept plugin for Obsidian and am currently testing out if built-in and in-text expansion has merit over the templates plugin and other expanders.
I don’t know yet!
Demo

Settings
Currently limited to 2 keywords (to start testing)
Repository
Anyways, if you want to test yourself, here’s the plugin
Let me know what you think!