This idea has been in heavy rotation in communities and groups and the answers vary a lot, just like the community. The premise itself is flawed from the very beginning, differentiating front development as easy and back end development as hard.
Moving past that another question arises: what language should you choose?
The answers go from PHP to Ruby, to Python and often enough to Node.js as well. Of course you have to take into account that everybody has a different learning process, so it depends a lot on how do you approach the language you choose. For beginners choosing the easy or let’s say approachable choice would be fine, but learning something useful is far more valuable, even if it’s harder.
This is one of those never ending debates, and the truth is, it’s not meant to reach a bottom line, the value of it all is the debate itself. Which language should you choose after getting a good grip on the front end side?