No worries. You're in the majority you know.
And your completely right about people filling a checklist, getting in line behind 12 others for the required Insta shot, etc. Much of popular travel has become just another form of consumption. Like Joey Chestnut scarfing down popular international photography locations instead of hot dogs.
There are a lot of historic places that have succumbed to the tourism demands of access, residency, and easy money that pays better than working a real job as a local. Florence actually is an amazing place with fantastic art and history. But being submersed in so many tourists at once (and particularly all American ones), it can feel more like the Venice of The Venetian in Vegas than the one in Italy.
Granted, at least the Venice canals are clean and nice in Vegas.
Even so, if you haven't gone once, it still might be worth going. For just once at least. And at least tempered with the expectations that it's going to feel more like a theme park at times, depending on where you go. As Andries points out, Rome is a little better because at least it seems to have the size and local culture to better hide the hoards of tourists who come through daily.
And do it your own way.
Two weekends ago I was reminded of how great it was to go to someplace off-beat. And I shouldn't need reminding, but there it was. Mixing in surprises where there aren't tourists can salvage everything if it becomes too much. I'll explain my example...
We spent a few days visiting the small, ancient town of Beja, Portugal, about a two-hour drive outside of Lisbon in the Alentejo countryside. The excuse was largely bureaucratic: I needed a new photo taken for my Portuguese driver’s license, and their DMV was going to be the most efficient.
It was a revelation. An old castle town with a multi-layered, rough history that went back to the Celts as a strategic location in the 3rd/4th century B.C. Julius Ceasar named the settlement “Pax Julia” in 48 BC in honor of it being where he made peace with the Lusitanians. And from the Roman architecture that remains, add the Visigoths and their art/architecture, the Moors, the Christian Reconquista, and additional layers of Gothic, Medieval, and Baroque architecture on top of that. The rural town with virtually no tourists was an archeological lasagna.
It was very much what I enjoy about Portugal. Despite it's imposing 1253 castle, where the town depopulated due to waves of deadly battles between Moors and Christians, it's a place with no real "the thing" you have to see here. It's all about getting lost in the streets and discovering new surprises, large and small. Eating at casual taverns with rustic, simple but fantastic food.