Irsay reportedly said they didn’t plan to extend him. I’m not sure if that’s just meant to be they aren’t extending him yet or they plan to let him enter free agency after his rookie contract his up.
Irsay also responded after the report saying “We’re not trading Jonathan… end of discussion. Not now and not in October!”
Running backs are no longer appreciated. Part of the reasoning is that they rarely have long careers. They take too much punishment. Also, rule changes make most teams pass heavy. And, unlike most positions that take a year or so of development, rookies often step in and play well. So why extend them? Just keep finding replacements on cheap rookie deals.
Edit: Not my opinion, simply trying to explain owner/GM reasoning.