This is TERRIBLE advice.
In a matter of seconds the person who compromised the system could have installed any type of software without giving any indication whatsoever to the OP.
Every one of their passwords is now compromised. The system may have a key logger or other malware installed. This will allow the hacker to gain full knowledge and access to everything on the system now and in the future.
That of course includes all the tax paperwork, identifiable information, Bank records, bank accounts, retirement account, crypto accounts, Google accounts, Facebook accounts, and Roblox accounts.
A person’s entire life is on their computer, and you don’t have to be rich, famous, or important to have your identity stolen, your bank accounts wiped out, and your financial life ruined.
I don’t know about you, but if every dime I have and every dime I will earn is now in danger, I’m going to do something.
To the OP, your friend definitely needs to clean their computer and (only after cleaning) change all their passwords.
If you change the passwords on the same PC before cleaning, you just gave the hacker all the new passwords.
There is every chance.