Just to put this in context:

There’s only so many ways to turn a bunch of files into one - mainly, you stick them back to back. Easy.

Then, there’s an infinite ways to compress that file… You could come up with you own method, but what good is that? It’s better and smarter to use a format already supported by your users

So of course most bundles are the same archive type under the hood. Everything from backups to installers - you shouldn’t be inventing new formats without a damn good reason