Long term, yes - a BEng or MEng plus a maintenance licence are not a bad thing to build a senior management career on.
And certainly having a maintenance licence could be of considerable value in an aircraft design role.
But a MechEng degree as I said previously is of at-best minimal value to a maintenance engineer. It's just the wrong skillset.
Seriously, either give up and study what you actually want to do, or complete the degree and then seek a job that uses it.
G