What amount of tantruming is normal?

My son will be 2 this Saturday and his behaviors started getting bad around 19 months when my daughter was born.

He is having 5+ tantrums a day sometimes lasting 20+ minutes. He’s hitting himself, throwing toys trying to attack his baby sister and the dogs, throwing himself on the floor screaming non stop and hyperventilating and recently started pulling his hair. Sometimes it’s triggered by not getting what he wants and sometimes it’s something like the baby crying or the dogs barking. Everyone is telling me this is normal but I really don’t have anything to compare it to as he’s my first. I have tried everything (aside from giving in to what he wants, because I’m not giving in when he behaves like that) we try hugging, rocking, speaking softly, ignoring, taking a “break”, distracting. It’s like he just has tunnel vision and eventually tires himself out.

I’m going to bring it up to our pediatrician in 2 weeks at his checkup. But in the meantime what are your experiences?

For reference he is not delayed, he is speaking in full sentences but I understand that he’s still not able to fully communicate how he’s feeling