Today 2019-11-06 the problem result as solved but it's not.
The shop I can't reach are jacksepticeye.com and markiplier.com, are youtubers with 20 milion + subscribers, for me it's impossible contact them to tell them to change the server settings. It's a problem Shopify must solve it's own because not everyone will use the solution previously given.
I may need to use the shop on that sites, please solve this.
If this can help, I found your "The 50 top Shopify stores for inspiration" list and I realized I can reach only few shops. From that 50 I took the first 20, following I show you which one I can reach and which not, hoping you find out why some can get through and others not solving the problem: