Long-lived TCP connections against a real-time simulation on the one hand and short-lived HTTPS connections to a website on the other hand are two very different things.
EVE is very frugal on network bandwidth but doesn’t tolerate well packet loss, excessive latency or timeouts, since the universe simulation has moved on. Also see my comment above about issues Virgin Media users in the UK have had.
I never said it was your ISP, as I have repeatedly stated there is a verified network routing issue between WOW! and Cloudflare that both companies are deeply engaged in resolving. Everyone is committed to fix this.