That image is stupid.
English is one of the easiest languages in the world.
Says who? I only speak one language but of those people I know who speak more than one they say English is very difficult. It's probably very hard to gauge what is the most difficult language though, especially if you don't speak at least several.
Says anyone involved in multiple languages. I myself know three now. Learning German is much harder than English for me.
The hardest languages would be Japanese, Chinese, Arabic and Korean according to some sources. One needs over 20k hours to become proficient in one of them (use Google). I've specifically used 20k, even though the source said 22k, due to this depending on every individual.
That's over 833 days.
Now if I compare this to my personal experience:
If I factor in primary and high school in addition to the time spent on the forum it's probably less than 200 days. I think that I'm fluent/proficient in English (or at least good enough).
I'll still leave this up for debate. Some people just have a hard time learning languages. Some have a hard time learning English. It depends, as I had no trouble learning any language so far.