Fish sticks come to mind
That’s what I was going to say. My favorite as a kid was ABC’s & 123’s (pasta shaped like letters and numbers) with mini meatballs. I bought a can when I was in my 20s just out of nostalgia, and couldn’t stand it. It just tastes overly sweet as an adult.
I thought of fish sticks too. But although I don’t really eat them as an adult, I don’t think I’d dislike them. But if I had a choice my preference would be a proper battered and fried fish-n-chips style fish.
I went through a phase where I put ketchup on everything. Nowadays, I’ll still occasionally have it in French fries, but that’s about it. Certainly not on, say, peas.
There was also a time when I thought that root beer and orange pop made a great flavor combination when mixed together. Today, I can’t fathom why.
And not exactly “childhood”, but when I was in grad school, I’d have a package of ramen for lunch nearly every day. Nowadays, that’s way too salty for me.
I haven’t had Fish Dicks since I was a kid! We ate them once a week growing up.
We ate things like Frosted Flakes and Captn’ Crunch. I wouldn’t eat anything like that now.
Candy corn. Just way too sugar these days.
Hostess hasn’t been the same since the bankruptcy. Suzy-Qs used to be squelchy deliciousness. It’s stodgier now.
Hormel chili. I can make better without much effort.
This one’s a little weird, but Grape Nuts. For some reason I actually liked them when I was a kid. Then I tried them as an adult and couldn’t stand them. I have no idea why I liked them as a kid, but I did.
I was a picky eater as a child and had few favorite foods. There are foods I ate a child that I eat as an adult. Fish sticks…Yum.
Yep, me too.
Well, it was tinned spaghetti in (alleged) tomato sauce with meatballs where I come from. But still, absolutely not.
And to add to this diverse list:
Cakes - these days I don’t like them, but I would eat them if I was really hungry; but iced cakes - god no! And back in the day I would pick the icing off cakes to savor it…
Milk - can’t say I ever loved it, but we used to drink it all the time. Haven’t touched it in many decades. And I genuinely loved evaporated milk - the mere thought horrifies me now.
Apples - we used to go scrumping for them. With the exception of russets I would not eat an apple now.
j
These.
https://www.walmart.com/ip/Musselman-s-Red-Spiced-Apple-Rings-14-5-oz/29891913
I also remember liking mincemeat pie but I tried some of it later in life and it was terrible. I think recipes vary quite a bit for that, however.
My favorite little packaged cake was the Nickles Banana Flip. They back!
And I used to open a box of Jello granules and eat it right out of the box.
And let us not forget the lowly circus peanut.
Similar shift in appreciations to what everyone else is reporting, different specifics perhaps.
Kook-Aid. bleagh! Too sweet by far and fake taste otherwise
Breakfast cereal with milk & sugar. Uh uh, no way.
Commercial (sugar-laden) peanut butter on white bread. Long since switched to the “natural” kind that doesn’t have freaking sugar added, or that weird emulsified oil treatment to keep them blended. Not a fan of styrofoam white bread either.
Hi-C / Hawaiian Punch. See the above entry for Kool-Aid, although a step up from that at least I guess.
Yeah, got me wondering, too. I don’t think they’re Kanye West, though. Not crazy enough.

And let us not forget the lowly circus peanut.
I can still eat a few circus peanuts.
Mine: syrup and peanut butter. Spread peanut butter on a plate, cover it with syrup, and scoop it up with bread. Just thinking about it makes my stomach hurt.

Hawaiian Punch.
Dang, completely forgotten about that. We drank tin after tin of that stuff. As I recall, it came in a quart sized can, (approx) and we had to open it with an old style can opener.
When I came home from school I used to spread slices of white bread with sweetened condensed milk and sweetened shredded coconut and stick them under the broiler a couple minutes. Just the idea makes my back fillings ache.

As a kid there wasn’t any kind of candy I wouldn’t stick in my gob but as an adult most things are way too sweet for me.
I’ve written here a number of times that I ‘outgrew’ my sweet tooth in my 20s and am pretty sweet-adverse today so there are a lot of things I don’t eat anymore. Bring back post-meal cheese!

Grandma would sometimes buy us sweet cereals, like Cocoa Puffs.
A big treat when visiting my grandparents a few states away was the sweet cereal. Mom didn’t allow it but grandma did . She’d mail us a box of ‘sweetie’ cereal on our birthdays. Interestingly, grandma wouldn’t buy us toys with guns (GI Joe, Star Wars, etc) but mom was ok with it.

When I came home from school I used to spread slices of white bread with sweetened condensed milk and sweetened shredded coconut and stick them under the broiler a couple minutes.
That actually sounds great. The next time I open a can o’ milk (probably for a Key Lime Pie), I’m going to try this.
See, I never lost my sweet tooth. I still have a bowl of cereal every morning, and during the last year, my “Uh, oh, I’m getting depressed; better binge!” food was a Big G Snack Pack sampler, with Trix and Lucky Charms and Golden Grahams… yummm…

My parents would never buy them but I would have traded just about anything for some Bugles Corn Snacks as a kid.
By the time I got old enough to buy my own they were just overly salty, overly greasy nastiness.
I just finished a bag. A giant family sized bag. Nothing finer for stuffing with Garden Veggie Cream Cheese.
I concur about Hawaiian Punch. Simple sugars, vitamin C, artificial flavors. I used to chug it by the can. Now it’s just dreadful.
Space food sticks. Had to have one in my lunch for school. Damn, they were dreadful. But it was SPACE FOOD!