It always does, and there is no way around it. Low interest rates are good for borrowers and bad for savers. It’s exactly the reverse with high 3/6  BIS central bankers' speeches  interest rates: they’re bad for borrowers and good for savers. But the ECB would not be fulfilling its mandate if these effects kept it from securing price stability.
Observance of the MREL is to ensure that eligible liabilities can be written down or converted into equity in a reasonably orderly manner if the institution is failing and is systemically important. In that case, it must be recapitalised and continued in a new form. It will take some years before the MREL is fully built up.