Abcbitss is imitating the username =>
ABCbits.
Regardless of the motive for making the account name as similar as possible, it should not be justified. It looks like they want to ride on the fame of the name, without building their own reputation.
I don't think events like this are accidental, but imitating users who already have a good reputation. Because if it's really accidental, it's unlikely that it can be like that, especially if it's just a difference of one letter or an additional character on the back. This is obviously potentially confusing for other users, especially those who are new to the forum.
In addition, actions like this can also open up opportunities for more serious things such as pretending to be someone else, spreading misleading information, or even scams if left unchecked. The reputation on Bitcointalk is built over the years with effort, so when there are accounts that try to resemble in this way, it clearly ruins the ecosystem.
In my opinion, things like this should be dealt with immediately so that they do not develop further. It is better to prevent it from the beginning than later there will be a victim because of misrecognizing the account.