Created an MR with the basic changes. See https://git.drupalcode.org/project/...

Created an MR with the basic changes. See https://git.drupalcode.org/project/bootstrap_sass/-/merge_requests/5.

With these changes, npm install works now. However, it shows deprecation notices for a few other packages. Would you rather I create a new issue for that or push updates here? FWIW, I updated all packages in my custom theme (and other improvements). Everything works well.