Google/Gmail: Turn off less secure app access

I got an email message (below) that appears to have been generated by Google.

Why now ??? Is there something I need to change or should I just stop using Gmail ?

So, this posting is really more FYI.

If more comes of it, I'll update this note.

Navigating the Google Account, however, offered no further explanations or options, other the deleted the devices I am using. I hope this is just over-reach on Google's part, but it appears to be new round of annoying and innocuous "security messages".

I haven't changed anything I'm doing for months. I managed multiple email accounts for business and personal work and I have never seen this warning before. It implies the "OS X" has access to my gmail, calendar and other documents. And, what's wrong with that ?

The only relevant searches all came from the Apple community.

====================== Email Example ======================

From: Google<no-reply@accounts.google.com>

Subject: Help us protect you: Security advice from Google

I'm running Mac OS X 10.13.4 (High Sierra) on my desktop

and 10.12 on my MacBook.