Muenster cheese.
Another vote for Honeycrisp apples - my mom (89 years old) said they tasted like “apples used to taste like.” I can’t judge - I used to always eat red delicious and granny smiths - but I do really like honeycrisps.
For me, the one that was a disappointment recently was Nabisco Graham Crackers. The new ones taste very cardboard-y to me. I think it’s a reformulation rather than a change of tastes on my part. I recently got my hands on some Cote d’Or chocolate after not having had any since the early 80’s and it was eerie to me how it instantly tasted identical, even after more than three decades.