I received exactly the same email with a different sender ("Anna Roland", a resident of San Francisco, California) and was also left quite paranoid by it. The email had an combative tone and felt like a legal threat.
You can avoid snaps by using Synaptic Package Manager. I learned this the hard way after installing Xubuntu 20.04 and finding every piece of software I installed from Ubuntu Software Center was either a slow, buggy or completely broken snap image.
I really dislike the way snaps create disk partitions. When I run $ df I want to see what I defined during OS installation, not a dozen nasty snap mounts. An application misusing fundamental system features like this feels like a violation of some UNIX principle.
The author should cite the article(s) that claim vegetarian diets alone will save the planet - this is clickbait/trolling. I'm a vegetarian and make no claim that being so is going to save the planet - it would help if we all were but it's definitely not a silver bullet.
There are many lines of argument to support meat consumption (all of which are easily refuted). Justifying it via a genetic hierarchy is one of the sickest.
I've been a strict vegetarian for close to 5 years. While I support any reduction in meat consumption, grading the edibility of animals by our perception of their intelligence is Nazism.