Technique may improve (at least until arthritis, COPD or other debilitating illnesses of old age set in), as may professionalism and learning few tricks of the trade. Voices will start to go - that can be managed to an extent by changing their style slightly, or by employing musicians who can drop the song down a few keys.
But - the creativity and drive - and often the anger - are the things that make their career in the first place - and that doesn't improve with age. That's why most bands' first couple of albums are usually their best (and before anybody mentions The Who, The Beatles, or any other band/artiste that is a bit of a favourite of theirs, yes, I know there are exceptions). Hence the use of the word 'most'...................
But - the creativity and drive - and often the anger - are the things that make their career in the first place - and that doesn't improve with age. That's why most bands' first couple of albums are usually their best (and before anybody mentions The Who, The Beatles, or any other band/artiste that is a bit of a favourite of theirs, yes, I know there are exceptions). Hence the use of the word 'most'...................