I asked my friends who are into Johnny's a while ago, and they all say it's mostly Toma's newest (eg: HanaKimi) fangirls that greatly exaggerate his "hardships". He's basically a Junior that never got debuted when he was the right age and now is too old for it so he'll never be in a boyband - but that's the same story of about a million other Juniors, and older JE fans have resignated to his fate a long time ago. New fans who don't know how JE works read his bio, find out he was once in those temporary bands with some Johnny's who are all famous and popular now and go "oh poor baby he could have debuted with NewS or Arashi or whatever but never did cry cry weep weep", as if the same thing hasn't happened with literally dozens of other Juniors who didn't get picked up either every time a band got debuted.
Now, I'm not into JE at all so I'm no authority to speak, but I think debuted or not, Ikuta's fine. If he was half as broken-hearted about the whole thing as fangirls make it sound, he'd have left JE by now. Kawano Naoki (Gekiranger's Long) and Nakamura Yuichi (Den-O's Zeronos) were Johnny's Juniors once and left when they noticed there was no future there for them, Ikuta could've left too if he was truly unhappy with his management. If he never left despite the disappointment of not getting debuted with his friends way back in the day, it's because he's comfortable there. And how wouldn't he be - he doesn't have the perks of being in a boyband, but he still gets great roles in great series just for being a JE boy, appears in every JE-oriented magazine all the time, gets money from advertising and ****... the kid's doing alright.