Minimal Plugins
Too many plugins on your WordPress, eventually is going to create a problem. Many plugins available are just for features that a developer should be able to create easily.
Necessary Plugins
There are plugins that are completely necessary such as a quality custom form plugin or WooCommerce and many others.
I only use the plugins that are beneficial to your site and other features I custom develop for website speed and extensibility.
Just an example of the plugin categories from the plugin repository.