Disappointing but really, another year of slow integration or AHL isn't the worst thing, if Jiricek is willing to accept it for what it is.
There will be a certain percentage of prospect fans who will or have already downgraded him and point to others from his draft class already becoming regulars, or being like "well he's another Czech kid doomed to failure" or simply assume that because its Columbus and he was a #6 overall pick and because a "no-name" like Christianson essentially took his top six starting spot - that this means the trajectory is all wrong.
But if you go back and look at the scouting reports - I would think this track and a slower burn to his development seems pretty much what should have been more or less expected.
Simon Edvinsson was drafted #6 overall as well, one year earlier, and spent most of last year (equivalent to Jiricek's current season) in the AHL. For whatever reason - maybe just trust in Detroit with Swedish prospects, it didn't seem to hurt Edvinsson's standing as a top 10 prospect league wide. There was more an atmosphere of "he's still growing into his body and his tools, he may need some time, but the upside is big".
The same should still apply to Jiricek, IMO. I think the downside here is not "it's taking Jiricek a bit longer to find his legs" - rather I'd be more concerned about a yo-yo effect of spot starting with low usage in the NHL mixed with demotions and call-ups over the year. I think he needs some stability - and maybe that should be "go to the AHL and dominate for a few months".