> Is revealing a PC account user name bad?

In short **NO**.Why?
<br>

 1. Well for starters your PC username is not a information that is
    unique to you.A lot of people in the world can have the same windows
    username.
 2. Since its not unique to a person like an email address where two
    people cant have the same email address an attacker cant gain much
    information or even tell with a certain degree that the username
    belongs to you and you alone.
 3. sure if that username of yours is your name itself the attacker
    might use that knowledge to further OSINT you but that's just about
    it

> Googling typically gets me back to the first two of these articles.
> These answers show that on a website it may be bad to reveal the
> username for the website account, because it gives malicious users
> needed information to try to crack an account. The "hacking" is
> rendered easier because the bad guy already knows where on the
> internet to try the passwords to crack the website account.

That is because a username in a website is unique and furthermore in a brute force attack two pieces of information are needed.An attacker could(if the website allows) try a combination of password since he already knows that the username is valid.

> Even if the user has port-forwarded remote-in software, one would have
> to know the internet address of the computer or the router, of which
> there's some 4 billion in the IPv4 space, and astronomically more in
> IPv6. Knowing where to start poking seems a lot harder.

The assumption that you make here is wrong.Never think that by hiding IP address you might be "secure". The concept of defence in depth has to be applied here.The internet is being scanned for vulnerabilities as you read this answer


> The logs therefore reveal the account user name to anyone who may
> download the log file. And everyone including non-authenticated
> visitors, can download log files. Some users obfuscate these path
> names because they feel that having their user names out on the web is
> bad.

In my opinion there is nothing insecure here,Plus you already say half of the people fake the names.There is nothing substantial to gain here for an attacker except maybe a bit of information about the person but THAT'S ALL!