Good point.
Incidentally, not everybody does rigorous projections, but how APPROXIMATELY tempered are your expectations (90, 80, 70, 60 solo tackles?)
I'll try to summarize some potential causes for hope/optimism and concern/caution.
Ogletree was himself prolific from the WLB position in 2013 & 2014, when Laurinaitis appeared to be faster and more agile. There have been a lot of tackles to go around in recent seasons.
While Tree is arguably more athletic (he has the makeup speed to finish plays even after initial misstep type mistakes), Barron imo has superior instincts. I always remember Sean Lee and Navorro Bowman because they were teammates at Penn State, in the same draft and among the most talented LBs in the league (when healthy). Also, they are almost poster children for not needing to be speed merchants (they ran plodding, lineman like 40s in the 4.7-4.8 range). Yet they are always making plays all over the field. That speaks to their instincts. Their recognition and football IQ to see how the play is unfolding before it happens is off the charts, and why they typically get to the ball carrier earlier than ostensibly "faster" defenders (at least in gym shorts, straight lines and controlled circumstances).
I think Ogletree will do well. But being a take on LB that stacks and sheds and can sift through the trash has never really been a strength, so shunting him to MLB is somewhat of an experiment. He has fine size, but has a tendency to run around blocks at times rather than engage them, which can get him out of position and take him out of the play entirely on occasion. Barron might take better angles to avoid blocks or get through them.
As to the dark side, if Goff is the real deal (though I expect more from him in future seasons than as a rookie), Gurley is stronger another year removed from his torn ACL, the young OL gels and avoids multiple injuries like recent seasons, the offense could do better, convert more third downs, sustain more drives, be on the field longer, which reduces tackle opps in general. Though, that could be countered if LA gets more leads, than the defense could have more opportunity to be aggressive (both LBs could be good blitzers and are former safeties that can make plays on the ball in the air, hard hitters capable of dislodging the ball from the carrier, etc.).