The theme does look good and the case for Gutenberg is compelling all the way up to speed testing the atomic blocks:

1. testmysite.thinkwithgoogle.com 8 seconds to load the site using 3G, estimated loss of visitors, 28%;
2. gtmetrix.com PageSpeed Score F(38%), YSlow Score D(63%), fully loaded time 3.4 seconds, Total Page Size 2.62MB, 78 requests;
3. developers.google.com/speed/pagespeed/insights/ Mobile Page Speed Average, Optimization Medium 64/100, Desktop Optimization Low 29/100.

Pingdom was too busy this morning to test, but it usually doesn't differ that much from the other tests.

It should be noted that the demo is SSL, so that's not an issue. Now I know that these demo sites are not often optimized in any significant way, but let's face it, they all should be if they want to make a sale.

I've experimented with over one hundred themes (many of them premium) and this is one of the worst ever even for a demo.

If you really want to sell Gutenberg, I would submit that you really need to get those timings up to snuff or come the next version of Wordpress there are going to be really agitated natives coming for you with pitchforks and torches.

I'd really like to see this succeed, but it seems that there are those who want to snatch defeat from success.