I have also been experiencing issues with Nord across all my devices as follows:
MBP M1 16": At times, not every day but far too frequently, very slow to connect to a new server after one has become slow and/or unresponsive. Randomly found myself connected to Portugal the other day.
iPad Air M1: Same as the Mac but actually a bit better.
iPhone SE 2022: Worst of the bunch, randomly off even though I have auto-connect on, very slow to pick up new servers, hate when I am forced to log back in. Have resorted to "reset network settings" many times, probably once every 3 months.
My sub is just about to expire as well and I may shop for an alternative or setup my own.