When I was a child, standing quietly as the hearse went by was usual, but some asked for singing. Funerals then were usually quite small - folk couldn't get time off work, but the factories and workshops allowed them to go outside as the hearse went by.
I think that clapping has become more common now, and I think that if it seemed the right thing to do then it was fine - we are all finding our way in these different times. I have been to a few funerals (pre-covid) where we clapped, to celebrate a life or to speed a soul on its way.
I am a bit sad as someone we cared about in our village has just died. His family, in a 'no-fuss' sort of way are just going directly to the crematorium. I would have love to have watched the hearse go through our village to pay my respects - silence, waving or clapping - I and others would have just liked it, but of course it is up to the family.
One of my great-grandparents, who had Gipsy connections, followed the tradition of having his coffin carried around many of the places he had spent time. I am too young to remember, but the family's account of stopping outside different pubs was a standard of my childhood!