Eli Zaretskii <eliz@gnu.org> writes:

> This seems to be a general complaint about package.el using Custom to
> save the data about installed packages. I see no arguments as to why
> it's wrong to use Custom for that.

There's two major issues that I have in this instance:

1) The user is barely notified that the variable is being saved. In other instances (such as the Customize interface), it's quite obvious that it's going to change your customize file. Installing/upgrading packages changes the file with no obvious notice or prompt (as the notice gets drowned out by the package install/upgrade/delete messages). It's also not obvious at all that your customize file is going to change from those actions (it hasn't since these actions were created).

2) The package list for a particular user can differ between different machines. This makes it annoying to share a config among the machine with something like git. I think this data would be better suited to a separate place where it's easy go gitignore it, like with abbrevs, recentf and so on. It's tied not only to the customization in the init file but also outside state (that is, any packages installed/deleted outside of your init file).