> We’re looking at ways to make the source link more discoverable and will update once that is done.
If Google was actually going to fix the issue, they would have said "we will make the close button direct users to the original site and will update once that is done" OR "we are changing the x (close) button to a ← (back) button".
"x" means "close" and "←" means "back". This is confusing UX at the least and arguably a dark pattern.
As a user, I hope Google do not implement either of your suggestions.
When I click the 'X' I don't expect to get a copy of the page that loads a bit slower, and I'd be surprised less than 95% of Google's users agreed with me (but by all means do a test).
And I don't want the close button changed to a back button. When I click on a search result I might then click one or two links on the publisher's web site before wanting to check out the next result on the Google results page. I want a single button that takes me quickly back to that search page - I don't want to have to click a 'back' multiple times (and maybe overshoot or undershoot my desired history position).
My current feature request is to link the "publisher domain" to the origin article, so that one can always click that to get there and use it to copy the link.
I've also sometimes been on a non AMP version, and Chrome has suggested "a version optimized for mobile". Clicking that has opened the AMP version and after reading the article, clicking the X took me back to the non AMP version.