Here's why Launchpad is/was the superior way to use a Mac for some of us:
First, the initial setup:
1) You change the number of columns and rows of apps shown in Launchpad with the following commands so that the apps you use 99% of the time fit on the first page of Launchpad:
Bash:
defaults write com.apple.dock springboard-columns -int <column-count>
defaults write com.apple.dock springboard-rows -int <row-count>
killall Dock
2) You enable the trackpad gesture in System Settings so that you can pinch with your thumb and three fingers to access Launchpad (I stopped using a mouse 13 years ago).
3) You move your most used apps to the first page of Launchpad, and place them at locations that make sense to you (for example, I organized the first four columns from the left in Launchpad to mimic the way apps are organized on the first page of my iPhone home screen, similar apps next to each other).
Now, we get to the most important aspects of Launchpad:
You don't use Launchpad
only to launch applications - You use Launchpad also as an app switcher whenever the app you're switching to is not currently the second most recent app you've been using (because when the app you're switching to is the second most recent app, the fastest way to switch to it is to press command-tab and release it so quickly that you don't even see the app switcher).
Using Launchpad, you can switch to apps based on their icon and consistent location on the screen. The command-tab app switcher gives you the app icon but not a consistent location of the icon. The command-space Spotlight app launcher method doesn't give you an icon and forces you to remember the app's name. I don't remember app names because macOS has taught me that I can launch and switch apps based on their icon and consistent location on the screen, without having to care about app names. Consistent location of the app icon allows you to learn where the app is and launch it very quickly with Launchpad, whereas the other two visual app switchers require you to first take time to find the app, from either a horizontal row of icons (when using command-tab) or a spread of window thumbnails (when using Mission Control).
Equally as big a problem as the inconsistency of app location in the command-tab app switcher and Mission Control is the fact that neither of those visual app switching methods is able to switch to an app that isn't running - Maybe you were editing a Numbers document an hour ago and want to continue working on it, so you decide to either press command-tab or do the Mission Control gesture, only to realize that for some reason you quit the app an hour ago (presumably System Settings are set such that documents and windows are restored when you re-open the app), so now you're staring at your app switcher not being able to accomplish your goal. In contrast, when you use Launchpad as your primary app switcher, it doesn't matter whether the app you're switching to is running or not.
Having the applications folder in the Dock doesn't allow you to control how many apps and exactly which ones are shown or exactly where in the grid the apps are located, and there's no quick trackpad gesture to show the grid.