Word, I was a bit surprised by the "email" section as well. As a better alternative to Gmail, I would have expected to see e.g. protonmail or fastmail, but instead saw... thunderbird, an email client? Which doesn't make a lot of sense
On https://prism-break.org/en/all/#email, they state "For more email providers, take a look at Privacy-Conscious Email Services. Please decide for yourself whether if you trust them with your data. For more discussion about safe email providers, please see issue #461.".
They even state that Thunderbird is a "Extensible, cross-platform email client.". The implied idea being to use Thunderbird to access a "Privacy-Conscious Email Service".
I use Gmail as an email client more than than I use it as an email provider because it has an External Accounts function. I apply Google's "App Script" system to my email to do things that you could do in Outlook's full-fat client or maybe in Thunderbird with some extensions.
If it is actually a malicious site trying to herd people toward exploitable behaviors it'd be following the Nigerian Scammer tactic of pre-screening by allowing simple errors to scare off more savvy inquiries.
This would go along with the rather crude emotional appeal.
That said, it hardly seems an efficient way to exploit people… though there are useful points. If you can get somebody credulous to use something that's compromised, and you're acting like a baleen whale and accumulating whole populations of credulous government-suspicious folks whom you've steered towards some mechanism where YOU can surveil them, that's got to have some usefulness.
People absolutely don't take into account the effectiveness of loosely manipulating entire populations in selective ways. You never need to select an individual and 'make' them take any action at all. You only have to cultivate the conditions for the outcome you want. Facebook might have discovered this first, but the idea sure caught on quick.