I have a website which has many photos served by Google Drive.
I have included the url in image tag like the following:
We are facing the same problem, from the looks of things, it appears intermittent and isn't always for the same file. We have successfully being hosting image files with GDrive for over a year now with little to no problems.
Email Received From Google on the 16 Aug 2016
Hello from Google,
We announced last year that we’re deprecating web hosting in Google Drive for users and developers. Our records show that you might have used this feature to publish a webpage or serve other web assets.
On Aug 31, 2016, we will discontinue serving content via googledrive.com/host/[id] and the webpages will not be accessible anymore.
As an alternative to web hosting in Drive, we recommend:
Blogger—An easy and free way to host websites. Firebase Hosting— An alternative if you’re using the web-hosting feature to serve static webpages with items on Drive. If you have additional questions or need assistance, please contact Google Support.
Sincerely, The Google Apps Team