it totally depends on where you are from if that is in any way relevant. for example, where i am from, i wouln't expect anyone to know it. so doing SOS in morse, would just get some frowns at best. and i couldn't conceive of a situation apart from total catastrophic civilisation meltdown where it would be needed. literally. and most cases which could occur to make that happen will render your electronics etc. useless so good luck sending it out...

if you're on a boat all day with a ham radio or such devices, sure it's useful to know. but in a big city or urban area with no general access to such devices? are you going to write dashes and dots on the wall???

not saying that it's useless to know. i learnt a lot of these things from my parents, and i would teach my children if i had any, but i can totally relate to people not caring about it in my area and finding it some niche interest for 'nerds' or so.