The way I see it, there will be two groups of people : Those who learn another language (maybe more than one other language) this way, and those who don't choose to get involved in language learning, on the grounds that having the whole internet available in their own language removes the need to invest time.
The first group will be glad that any language is now as free (financially) to learn on-line as Esperanto is now, as long as they have free access to the internet. Esperanto will still take 100 hours to master compared to 600 hours, for most European languages, and 2200 hours, for Mandarin or Japanese. And learning Esperanto first will still reduce that 2200 hours by more than 100 hours, as it does now.
The main difference, might be that both groups gain a greater awareness of the non-English-speaking world through the new availability of foreign sites in English. I think that has to be a good thing.