Diagnosing fsroot tree problems in new macOS installation after installing Vainglory via Steam

SUMMARY

Can Vainglory or Steam cause file system corruption or are new macOS installations already corrupt?

BACKGROUND

I've been having problems and suspected interval drive problems. To troubleshoot this I created a new installation of macOS on an external drive.

EPISODE

I took a break from troubleshooting and installed Vainglory (a game) via Steam (a game distribution platform) on the external drive. The next day when I ran fsck on the external drive it had one ExtenetRef physical extent Cross Check error and countless fsroot tree errors.

DISCUSSION

From what I understand fsroot tree is something about the file system, how the computer organizes information on the drive. I'm surprised that the external drive had those errors, considering it was a brand new installation of macOS and the only software I installed were Vainglory and Steam. So the question is, what caused the disk corruption in the external drive? Vainglory and Steam, or was the corruption already there?

Of course I'll troubleshoot this more tomorrow, but I'm curious what other people think.