Here's another take on this:

A bad attempted accent is a bad attempted accent, and that always raises a smile or at least a grimace.

BUT:

Many Scottish songs rely upon Scots language vocabulary or accent for their rhyme, or even to express accurately the sense of the song.

Occasionally, I hear an attempt to anglicise one of these songs where key phrases have been changed, or amended to substitute English pronunciation. That tends to annoy me more than someone attemting to use the song the way it was written. Please note that this doesn't apply to traanslation of a song into, say, German or French...

You can accuse me of having a double standard if you like, but I'd rather people attempted the words to get the rhyme/sense made.

For example, listen to Luke Kelly singing Scots songs.. he did great versions of "Tramps and Hawkers", and "The Freedom Come-All-Ye". He sings in his own voice, but uses the Scots words where they are need to make the rhyme.

At a recent session, a guy was singing "Ride On" - and he felt compelled to adopt a weird Irish accent, which was quite unnecessary.

However, at the end of the day, sing the song, sing it your own way, and enjoy singing it. And above all, don't worry about it. It's there to be enjoyed, not agonised over.