No it's not. Gmail fetches images when you open an email to read it. You can test this yourself using https://www.emailprivacytester.com.
The only thing Gmail does is hide your IP when it fetches the image. It doesn't hide the fact that you've opened the email. Which frankly, is the most useful piece of information to the tracker.
The email privacy detector is seeing Google fetch the image. In the HTML of the email the sent me the image URL points to a Google proxy link.
On subsequent opens of the email, the detector is not seeing the image being requested again.
Unless you were proposing the email server should download and proxy ALL images, even before the email is delivered. Some anti-spam clients already do a version of this, although it should be noted that giving an email sender the signal that you are eagerly reading all of their emails may produce unintended consequences.
> Unless you were proposing the email server should download and proxy ALL images, even before the email is delivered.
That is precisely what the OP proposed, and which you then stated is the way that gmail works.
I then pointed out that gmail does not work that way. And you have now confirmed that.
> giving an email sender the signal that you are eagerly reading all of their emails may produce unintended consequences.
That's the whole point of this. The moment the big providers implement "fetch on delivery", there is no signal any more. The spammers wont suddenly think, "oh look, our spam campagain is going swimmingly. 100% of our gmail, hotmail and yahoo recipients are now opening our email", and then continue along oblivious of this new major change from all the main email providers, thinking that all of their email is being opened.
