That too, though the point of using a distributed code control system was the purpose I mentioned. But even before BitKeeper getting in a tizzy about Tridgell's¹ shenanigans there was talk of replacing it because some properties of it were not ideal for something as large as the kernel with as many active contributors, and there were concerns about using a proprietary product to manage the Linux codebase. Linus was already tinkering with what would become the git we know.
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[1] He did a lot more than type “help” - he was essentially trying to reverse engineer the product to produce a compatible but more open client that gave access to metadata BitKeeper wanted you to pay to be able to access² which was a problem for many contributors.
[2] you didn't get the fulllest version history on the free variants, this was one of the significant concerns making people discuss alternatives, and in some high profile cases just plain refuse to touch BitKeeper at all