Waffle House lost some of the atmosphere once you couldn't smoke in restaurants anymore and there wasn't a thick haze hanging in the air every time you went inside one
You can always tell when a building used to be an IHOP because of the roof, same with Pizza Hut
I kinda want to nominate pizza chains, but I feel like the top 4 or 5 would be pretty obvious
https://imgur.com/WqDcNNq
https://imgur.com/89Z5jrB