Scenario:
a) I work for abc inc & my email address nameabc.com is configured in gmail for POP & "send mail as"

b) Now I leave abc inc & my address nameabc.com is deactivated

c) Every POP attempt must be getting an "auth fail" response. But I'm still able to send out email as nameabc.com

Though not a big issue as I can anytime do that from any SMTP server, but shouldn't Google deactivate or temporarily disallow mail being sent as nameabc.com because there are a number of auth failures.

comments?

I guess they should do this but probably don't since the "send mail as" and "mail fetcher" features aren't really linked.

As you say, it's not a big issue but ideally Google would do this. "POP authentication before SMTP sending" is used by many ISPs.