When I read about recommended Obsidian plugins, I install the plugins for future use. Most of the plugins are disabled. I have only just started creating notes. I have not noticed any performance issues. I just want to make sure my approach is not going to cause issues as my vault size increases.
To clarify, plug-ins that are installed but not activated shouldn’t affect performance. Once you activate them they will have some effect (how much depends on which plugins and how they’re used).