I don't see a really fair argument here for the idea of the Trill being boring...it seems people are confusing that with their opinion that the actual people who played Trill were boring, or not explored interestingly. And this of course leads to more Jadzia bashing.

I can understand if people thought that the writers didn't explore the culture to its potential creatively or that Jadzia didn't make it look very interesting (though I'd never agree with that), but this doesn't change the fact that the concept of the culture itself is definitely very intriguing.
In fact, I think it's one of the most fascinating and original alien races ever invented in
"Star Trek"...just the idea of a being that could contain the memories and feelings of several lifetimes is endlessly thought-provoking for its physical, emotional, and psychological implications. There are so many questions it raises about the capacity of an individual to maintain so much different knowledge, intelligence, and feeling all at once and how it defines the person's identity.
I can't believe someone could find the concept of a person constructed this way to be uninteresting. If you think the writers could have done more with it or come up with a better character to explore it through, fine, but those criticisms don't mean the idea of the race itself isn't interesting.