I’m another of the ‘never had garlic in the 70s/80s’ brigade.
My parents were a bit older (second marriage) and my DF had grown up in a poor household in south London before the war. His parents worked in factories. My DM was from a slightly better-off family, her dad had a professional job and her mum didn’t work, and my DM was certainly of a university level of intelligence, but being a schoolgirl in the 1940s-50s she was never encouraged to pursue her education and so just went to secretarial college because that was what bright girls did in those days.
My dad was very against ‘foreign muck’ in terms of food. He grew up eating egg & chips, liver & gravy, that sort of thing - a typical English prewar diet - and also had some issues around certain foods, so this is what he continued to eat as an adult. My mum was very open to more adventurous food but it wasn’t worth buying it just for herself (I copied my dad’s fussy eating, as a learned behaviour) and I’m not sure she’d have known what to buy, or even that our local shops would have had those ingredients. I do recall though on one occasion when she’d picked me up from uni at the end of term on her own and we stopped at a Little Chef or something. She asked the waiter for French mustard instead of English. We never, ever had anything but plain Colman’s English mustard at home and I remember thinking ‘How does she know about French mustard? [I barely knew what it was either] OMG my mother is a stranger to me!!’ 
Seriously it might have been the first time that I perceived her as a separate person with their own unique inner life, rather than just ‘Mum’.
My dad had a particular horror of garlic due to his food issues and having spent time in Italy during his National service. If my mum cooked herself anything ‘smelly’ she had to eat it in another room. She would make a (pretty bland) curry once a week, using curry powder, to use up the leftovers from the Sunday roast (usually chicken, occasionally lamb or pork; never beef as too expensive), which my dad would grudgingly eat but that was as exotic as it got. When spaghetti bolognese first became a thing in the 80s, she would sometimes make it just for herself, but no garlic or Parmesan as they were banned from the house.
At uni I dated someone who put lashings of garlic in his food. I learned to cook a couple of dishes and encouraged my mum to try it. She bought this one bulb of garlic and carried it home like it was prize caviar. She used a couple of cloves, enjoyed the meal and I thought no more about it. But when I went home in the next holidays several months later, she got all excited about the prospect of us cooking with ‘the garlic’ again. That was when I discovered that she’d kept the one precious bulb, untouched apart from the tiny amount we’d used, in a pot on the kitchen windowsill in the sunshine since my last visit.
Obviously it had first sprouted and then gone mouldy. She was furious with me for ‘not telling her’! I think she’d assumed it was like a dried spice and would keep indefinitely. She genuinely hadn’t realised it was a fresh vegetable. I was so embarrassed for her and didn’t know what to say. I’m upset thinking about it even now, thirty years later.