I just stumbled upon the following reply and this seems to be the most honest explanation for the changes so far:
(Highlights in the quote by me)
I certainly understand that a company needs at least to break even. Therefore, the mantra of »growth is key« seems logical. Less logical is that keeping the legacy site and therefore the legacy users, is considered stifling.
Therefore, after reading this particular reply, I assume, the great feature to have community courses for many different languages will most likely also be abandoned. There will be curated memrise courses and it is rather unlikely that memrise courses will be created for less popular / small / endangered languages as they do not contribute to growth as demand will be too low for these. Of course, I may be wrong, but as @BenWhately stated, rapid growth came when Memrise started with its own courses and rapid growth is the company’s main focus.
Ideas like the ones presented by @cos are deemed interesting, but do not contribute to growth and will therefore be ignored.
Side note: When reading this interview, it also became clear to me that the web version still being alive is a happy accident:
What was your biggest business mistake?
Not going purely mobile in 2010. We considered it at length but, because our only developer knew web and not mobile development and we already had a web prototype, we thought it would be safest to stick to the web.
Of course, I understand very well, that for many people in economically weaker regions mobile is the only option.