> Forgive my ignorance of js matters but how does adding packages improve backward compatibility at all?

The scheme is based on providing polyfills for deprecated browsers or JavaScript runtimes.

Here is the recipe.

- check what feature is introduced by new releases of a browser/JavaScript runtime,

- put together a polyfill that implements said feature,

- search for projects that use the newly introduced feature,

- post a PR to get the project to consume your polyfill package,

- resort to bad faith arguments to pressure projects to accept your PR arguing nonsense such as "your project must support IE6/nodejs4".

Some projects accept this poisoned pill, and whoever is behind these polyfill packages further uses their popularity in bad faith arguments ("everyone does it and it's a very popular package but you are a bad developer for not using my package")

I had the displeasure of stumbling upon PRs where tis character tries to argue that LTS status does not matter at all I'm determining whether a version of node.js should be maintained, and the fact that said old version of node.js suffers from a known security issue is irrelevant because he asserts it's not a real security issue.