Jiricek has a ways to go before he's even close to Burn's skating level. Again, definitely a top prospect and he is going to be a great defenseman, but if the skating doesn't improve there is a ceiling to how great he can become.That is the issue. I think with more time to focus on skating and strength he might get quicker and it won't matter.
In either case he is probably never going to be a Makar or Josi end to end skater, but I'm not sure that means that there isn't a path for him to become a top 5 D. If Brent Burns was a more attentive defender while scoring 70 pts a year, that's a top 5D. I can see Jiricek maybe doing that. The PPQB skills will have to pop if the skating doesn't improve.
His skating is just passable against Team Canada in the World Juniors. Not saying he can't improve his skating, but you can see how it limits him.