In reply to Anthony Hortin.

This leads to several problems caused by the default setting problem.

If it disables the widgets by default then that can be undesirable. Some people use the classic editor to avoid the block editor, but some user it for compatibility reasons, e.g. custom functionality from when they built their site they don't have the budget or knowhow to replace.

If it doesn't disable widgets by default then that means it's not enough to install the plugin. The first reaction will be that it doesn't work.

On top of that, automation can't rely on installing and activating the plugin, which makes automating it much harder and beyond the scope of some users until they gain certain developer skills, gatekeeping the feature.

There's also the argument that the two plugins are not very similar, and that the only thing they have in common is that they disable something block related. The block post editor is not the block widgets screen. But if they are the same, and if that's the case then why not make the classic editor a checkbox in the Gutenberg plugin? And merge the plugin that disables block patterns? What about the overhead of the code that manages all these settings?

In the end, a simple plugin with no UI that you install and activate is the simplest, fastest, and most efficient solution. There's also nothing preventing an all in one bundle plugin being put on the .org repo.

A final note, the classic editor does not contain the classic editor. It's just a chunk of code that removes block support from the default post types and deregisters some scripts. The actual classic editor itself is still inside WordPress core. I expect the widgets screen plugin is the same.