Bitcoin has had a number of forks over the years. The biggest one was Bitcoin and Bitcoin Cash.
Bitcoin seems to have won out in this fork, and is much more popular than Bitcoin Cash.
However, how was this naming scheme agreed? Why did Bitcoin end up still allowed to be called Bitcoin, whereas Bitcoin Cash needed a new name?
Arguably the fork that had the original name had a much bigger advantage in "winning out" over the one with the new name.
For example, Ethereum also had a fork and it was the original Ethereum that needed a new name (Ethereum Classic) and in that case, the new Ethereum (the fork we know now) was the one that won out.