Gotcha.
Okay, so we all understand that the reason you don’t have access to an ‘Elite Plan’ feature is because you don’t have an Elite Plan. There are always ways to see a prompt that is public, but the specific, easy, and convenient “View Source” feature is something that was added specifically to Elite plans and above, not something that was taken away from other plans.
As you can see, this was a new, added feature, released on 20th March.
Before that you likely used other methods to see the source, the actual prompt, such as discussed in Is it possible to view the actual prompt of a preset?