A few weeks ago I took over a website running 74 active plugins. The site loaded in 8 seconds, the backend was sluggish, and the admin had stopped installing updates — afraid that something would break.
This is not a rare case. WordPress has built a plugin ecosystem that makes getting started easy — and that is exactly how many sites turn, over the years, into a patchwork of dependencies that nobody can account for anymore.
My approach: three questions before every installation. First, is the feature truly necessary or just nice to have? Second, is the plugin actively maintained? Third, is there a clean way to do it without a plugin?
The result for the site above after 6 weeks: 22 plugins, load time under 1.5 seconds, updates running automatically.