I never watch videos personally, but that's more because most of them are terrible and don't help than anything (they either just talk about it and never show the actual product, or take 5 minutes introducing themselves before the 1 minute demo, etc.). I'm sure it could be done right though, but I'd bet other people have also been trained not to click videos.

The email gate sounds good (except don't generate a password that will then be visible in plain text, generate a one-time login that can't be reused after a certain amount of time and give the user the option to set a password later if they want one); sites could expire after a bit and a real account (where the site doesn't expire) could only be created if/when the user chooses to create a password and you can't save or use features that could trigger emails until you've verified your email or something.