You don't need any plugins to be productive in Obsidian. But boy does a plugin like Dataview make life easier. Being able to run SQL-like queries on your notes was a game changer for me.
Other than that, the only plugin I use on a daily basis is Templater in combination with Quick Add, which lets me create advanced templates which can be executed with keyboard shortcuts. Starting a new work meeting? Hit a shortcut and I have a populated meeting note in the right folder, with today's dates etc. I have about 20 such templates for various things that I do frequently. It makes for tidy, structured notes which I can easily find later.
Other than that, the only plugin I use on a daily basis is Templater in combination with Quick Add, which lets me create advanced templates which can be executed with keyboard shortcuts. Starting a new work meeting? Hit a shortcut and I have a populated meeting note in the right folder, with today's dates etc. I have about 20 such templates for various things that I do frequently. It makes for tidy, structured notes which I can easily find later.