Humans seek adventure, but not at the detriment of their lives. We are not superheroes and we know, this realization is what keeps our adrenaline up. If there was a wormhole(a dimension where dangerous animals live) on the earth and I'm invited to take the adventure, I'll decline such an invitation with no second thought. I love adventure, but I can't put my life on the line for it. I'll prefer to play safe to taking a 50/50 chance for the sake of fun and the excitement of escaping a near death experience.
Here is why I wouldn't go to such a dimension. Animals like dinosaurs are not human friendly. In their attack they're calculated and probably have a certain sense that makes them catch up with their prey easily. While having the dinosaurs chase and the fun of survival among wild animals is awesome, surviving 5 days looks almost impossible. Why live in a world where flight becomes my daily routine when I can drop the adventure for something more daring. I love my life and can't trade it for a visit to a dimension with extinct animals.

Image generated using Gemini AI
They're extinct because they were probably wiped out by humans or certain things. Seeing a human visit their dimension after they've left earth becomes a call for fight. I can't run as fast as a dinosaur, I am not as strong as they are, even if I had something to protect me, I may not be able to survive in a land filled with them. They'd welcome me gladly as part of their next meal. I know it would be nice seeing a dinosaur, plant, or a living creature that went extinct, the thrill seeing something from our fairytale, but it's not worth the risk.
Lastly, those animals and plants had gone extinct for a reason, probably because they were harmful or dangerous to the human race and needed to have a dimension of their own. Answering the call to visit such a dimension would be like a self-inflicted wound that leaves a regret at the end. For the wormhole on earth, I'd rather set up a camera that captures their world from a distance rather than visiting to have a realistic experience with them.