This ranking of Fred's portrayals notably includes whom I consider to be the worst portrayal of any main character in the franchise. My favorite is already pretty clear from the beginning, and I would be very surprised if somebody picked somebody other than him, but nonetheless here are my rankings!
6. Freddie Prinze Jr.
While I don't want to come off overly negative, Freddie Prinze Jr. is hands down the worst portrayal of any main character in the history of the franchise in my opinion. He comes off like a narcissist who thinks he is the coolest man to ever exist, and admittedly, people who are full of themselves is one of my least favorite personality traits. I feel Be Cool, Scooby-Doo! pulled off something similar so much better. In that series, Fred is a bit of a control freak. However, it's executed in a funny way in that series, whereas here he just comes off like an unlikable jerk. This goes below Marla Frumkin levels of bad in my opinion, and is truly the bottom of the barrel for portrayals.
5. Pierce Gagnon
Like I said when I talked about Ariana in Velma's rankings, I hope this ranking improves when I see Scoob! Holiday Haunt. I really have no quips against this portrayal of Fred, other than it's just kind of unmemorable compared to the other four.
4. Zac Efron
Similar to his younger counterpart, the only real issue I had with Zac's Fred portrayal is it comes off a little flat. Granted, this is miles above Freddie Prinze Jr.'s portayal of him and I did really enjoy him in SCOOB!. However, compared to the other three SCOOB! voices, Zac's was probably my least favorite. Guess he just needed to get his head a little more in the game (bonus points to anybody who got that reference haha).
3. Robbie Amell
I think this was a much better execution of Fred, even if it still wasn't amazing. Having Fred be a macho jock feels at least like a more natural characterization for Fred than making him into a complete jerk like they did in the first two live-action films. I also recently saw Robbie in another show, Upload. I really enjoyed him in that series and would highly recommend it.
2. Carl Steven
Guess it just goes to show iconic #1 is when Carl Steven makes it to #2. I love Carl's portrayal of the more zany, wacky Fred. He gets the voice down perfectly and is my second favorite of the child actors in A Pup Named Scooby-Doo. However, I do always feel bad now when I see his name, since he had such a sad life after this show ended and died alone in prison in 2011.
1. Frank Welker
Those two words are all that needs to be said. He is Fred and I'm going to be really sad when he retires, which hopefully is a long way away.
If anyone else wants to share their rankings for Fred's portrayals over the years, feel free to do so in the comments!