Idk if you're just way low on Doncic or what but I could not be further opposite on evals. ha. 1. Ayton has bust written all over him. Yes, he has physical talent, but he sucked on defense in college. Very few guys become good on D in the pros if they sucked in college. KAT was actually fairly good on D in college and now he sucks at it in the NBA. Ayton has a short wingspan which won't help him make an impact on D. Also, he doesn't really take over games the way you want to see from such a physically dominant player. I can see Ayton being a guy who gets stats and highlights but doesn't make his team a whole lot better, or at least not a driving force in his team being a top 4 seed. Also, teams like the Celtics, Warriors and the Rockets are making it hard for big men to stay on the floor. The Center position is becoming less and less valuable as the game evolves.
Taking Porter over Doncic would be insane, IMO. Porter can score. That's about it. He's not a good dribbler, and would have to improve a ton in that area to become a #1 scoring option for a team. He doesn't score efficiently; he jacks up a bunch of jumpers at not great clips. He's not very physical, doesn't rebound or defend all that well. And on top of all that, he's got serous back issues.
Meanwhile, Doncic is playing in a league that plays way better basketball than college teams averaging 21, 7.6 TRB, 6.7 AST per 36 minutes while shooting 46/31/80 at the age of 18. I get people have concerns about his athleticism (and the athleticism that is currently guarding him), but he's incredible in the PnR, averaging 1.258 points per possesion, and knowing how running the PnR doesn't require great athleticism. He's 6'8 and could still grow some. His length will help make up for lack of athleticisim on D.
I'd be picking Doncic #1 without any hesitation, but the range of opinions is what makes drafts fun.