Halacha and authority to disagree with predecessors

Hello, Honorable Rabbi Michael. How are you?
Based on what I've read from your articles so far, I would appreciate it if you could explain to what extent you believe that even a person in our generation can disagree with the previous ones? That is, if I have reached a different conclusion on a particular halakhic issue than a certain first, or Amora, or even Tanna, have reached – can I disagree with them and say that they were wrong, and follow the path I saw fit as long as I maintain the halakhic principles?
2. A question that is a derivative of the first – are the halakhic principles the only thing that has received formal authority and cannot be disputed or ignored when ruling on the halakhic law of any Jew?
3. When does the rule "a void taste, not a void regulation" apply? It sometimes seems ridiculous to cling to something that no longer exists today in changing circumstances.
Thanks in advance!