It had definitely changed by the early 80s - as kids in the 80s we had orange juice in cartons at home as a drink, plus the clear brown apple juice which everyone had because cloudy apple juice wasn’t yet a thing. Both from concentrate of course! And pretty ubiquitous for kids as a drink in the 80s, to the extent that I know a fair few contemporaries now in their 40s whose teeth were ruined by fruit juice because all our parents erroneously believed it was “healthy”.
But I knew about the orange juice as starter thing because occasionally we stayed in guesthouses or hotels by the sea for holidays, and there you could always have a starter of orange juice. I remember staying in a really old-fashioned seaside hotel in Devon in 1984, all very Fawlty Towers, and being gobsmacked at the starters being orange juice only! It was a staple of old-fashioned guesthouse menus for quite a long time after orange juice was considered quite ordinary. It was always smooth juice, though - the days of “juice with bits” were quite a way off.
And the soups of those days weren’t at all chunky like most soups today. You’d typically get Heinz cream of tomato watered down really thin, or bouillon style soups - my favourite as a kid was the “Florida Spring Vegetable” from a packet, which was v v 70s and was basically yellow bouillon with tiny bits of tasteless freeze-dried vegetables floating in it, including teeny tiny dried-up peas. I loved that soup (but I fear that it was absolutely vile and would probably give one instant salt poisoning these days…)
My mum all through the 80s did a variation on the melon starter for special occasions like Christmas dinner - melon with either port or cranberry sauce was a favourite one of hers! To be fair she was a very good cook, and often ranged well beyond the usual 70s/80s recipes.