I’m not quite as particular as my father was - mealtimes could be a trial, with the constant exhortations to do, or not do, this or that, but I do still think they’re important, and am very glad I was taught how to behave at the table.
A friend of ours, OTOH, who’s no longer with us, had the most appalling table manners - among other things, shovelling food in, eating and talking with his mouth so full - there was always an argument between dds as to who was not going to sit opposite him at the table! It was honestly gross.
Evidently he hadn’t been taught as a child, but he’d been very successful in his career and was very sociable, so how on earth he hadn’t picked up acceptable manners along the way I will never understand.