That's true. The roster is set up to run on default 60/80 auto subs, so rookies after year one come in on the default system. No big deal. Many people have been using default anyway since the auto subs are FUBAR.
Biggest thing you will notice with the roster is a good rotation from the RB position for human and CPU without subbing your O line or disappearing players. Worst case scenario, you see less rotation at RB as some of the rookies develop into starters after a few years. There are still stamina issues to deal with on default auto subs. Many of the drafted rookies I have seen have some stamina issues of their own, so that mitigates the issue as well.
I don't see it as a show stopper by any means. It is a great roster (has a lot of appearance and equipment edits in there as well, if you care/ notice that stuff) and if I get a few years worth of good realistic RB rotation out of it before it reverts back to the EA broken garbage it'll be well worth it.