Starting out, I found MEL very accessible to dip my toe in.
One big advantage, as a beginner in scripting, is that every action you do gets printed out in the Output Window inside Maya. So you can just do the action once, and Maya gives you the code on how to repeat that action for free.
That made it easy to learn how things worked, and just copy/paste code together.
However, MEL is a bit stupid to write more complicated code with, so I quickly felt hindered once I wanted to be a bit more creative with it. Which also affected my motivation to pursue more scripting.
A year later, I randomly started picking up a bit of Python, and it was the best decision I've made in a long time for my CG 'career'. As soon as I got the basics down, it felt a lot more intuitive and fun to work with. The MEL commands are easily translated to Python, and the documentation is excellent. It was a lot easier to write complex scripts, and within a few months of first picking up Python, I had written UIs which automated my entire animation pipeline, speeding up me and my classmates project significantly. That would not have happened if I stuck with MEL.
So yeh, learn a bit of MEL to begin with, but jump on Python as soon as you feel ready for it.