I was first in Dubrovnik for my 40th, 11 years ago. Late September. Yes, there were tourists (like us!), but it wasn't overrun. You could get on a bus - and local men would automatically give up their seats for older people/women. It felt fairly traditional outside of the main areas, and you could wander around.
That week, they happened to be filming the part of Game of Thrones, where Cersei did the Shame Walk, so parts of the city were closed off in the very early morning. (Yes, I'm a GoT fan, and it intrigued me, that I wanted to visit that beautiful place!)
We went back about 18 months ago, in early June 2024. The days were hellishly busy. 5-6 cruise ships in, and some absolutely vile people from them (mainly British, sadly....) I sat down on some steps for a rest, as was on crutches at the time, awaiting a knee replacement, and letting my friend climb up to the top. Whilst I waited for her, two older women from Glasgow sat down next to me, and as I'm also Scottish, we started chatting. OMG! They moaned there was 'nothing to see', the 'food was terrible', and that there was 'too much walking'!! All things I vehemently disagreed with! In the end, I suggested they might consider staying on the ship in future!
Anyway, there were huge groups of tourists from the cruise ships, being taken around the tiny streets, blocking the way for others. The tour guides didn't sound Croatian, so not bringing a local context to things; and they looked miserable too. It was stiflingly hot, TBF, but if that's a cruise ship holiday, I'll pass... (I realise this isn't the point of this thread, but I was on a roll there!! 😁)
I'm not sure these type of groups really add much to the economy of the place, and just completely overcrowd the streets. Had similar experiences in Mykonos just pre-Covid, and it's totally put us off going back.