Why are there so many directories inside node_modules?

Question

npm

Good afternoon, I have not worked with NPM for a long time , I recently decided to make a project on Gulp .
I placed the file in the project folder: package.json
I typed the command: npm up
And I was surprised to find a huge pile of 40Mb folders in the created node_modules folder, although in theory only 4 module folders should have appeared there. see the picture below
So I think it's a glitch, if it's after the update. Did I do everything right?
package.json file code

{
  "name": "site2",
  "version": "1.0.0",
  "description": "",
  "main": "gulpfile.js",
  "dependencies": {
    "gulp-clean-css": "^2.0.13",
    "browser-sync": "^2.17.5",
    "gulp": "^3.9.1",
    "gulp-autoprefixer": "^3.1.1"
  },
  "devDependencies": {},
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC"
}

Answer 1

npm behavior has changed since version 3 https://docs.npmjs.com/how-npm-works/npm3