My wife has read most of his stuff. I know because I buy it for her. She says aside from Dracula, most of it is not great.
It's one of those firsts that established a genre.
I know Stoker didn't invent vampires, but they came into western English speaking culture through his Dracula.
Thematically it is of course a dogs breakfast of repressed sexuality, homosexuality, etc. All of which were taboo topics in the Victorian age. Which is precisely why the story works so well. And even today it still works. If you can get over the Victorian era biases, it's a surprisingly fresh and modern story. Which is why modern takes on the story are still interesting.
And of course, these topics are still playing a role. Just look at the current election round in the US where things like abortion and gay rights are still being challenged. And it's not just the US where these topics are used by populist politicians to gain votes.