I don't know where you're getting your data from, but just look at some random match lists, and tally up the #s of people going into Primary Care vs specialties. And OMM is only for the true believers.
For my graduates (and at 13 other COMs), the majority of them go into ACGME residencies.
About 2/3rds of my grads go into Primary Care. My students self-select for this. They DON'T tell each other white lies to make themselves feel better, they do this because they want to.
1/3rd of my grads get into specialties.
~5% get into ROADs specialties.
Maybe 1-2 kids every year go into OMT.
At another COM west of St Louis, ~40% of the grads go into specialties (AOA + military + ACGME), with ~5% into ROADs
So cut the bovine excrement. If you want to specialize as a DO, you can. You might have to work a little harder....are you afraid of hard work?
I don't foresee legions of MD grads going to rush into OMM training so they can get into an AOA residency. Time will tell.
ACGME IM, EM, and FM is not that hard to match into, but ACMGE Orthopedics, Radiology, Dermatology, and ENT, now that is another story. IM at elite research institutions is tough for a DO (Harvard, Yale, Hopkins, etc) as well.
I was looking at match lists from several years ago at my school. Someone from the class of 2010 matched into Dermatology at the Mayo Clinic, a top Allopathic program, which is unheard of for a DO, I think that was just a lucky outlier. I looked at recent match lists which did not look as good, I would be impressed if I get Internal Medicine at Mass General, I think that will be a very uphill battle, I would probably the first DO to match there.
At my school many of the people I know for a fact including myself were aiming for an MD school but did not make the cut for various reasons, I had the grades and GPA, but did not get in, and at least a third of my class had the same fate, so they chose DO. Maybe your school has a more primary care oriented culture than mine which I assume is the case.
Most top MD schools the ratio is 2/3rds specializing with less than a third going into primary care, its the reverse at most DO schools. Of course you have to work harder, but there is still an inherent bias at some academic programs against DOs much like there is bias against foreign graduates.
If 33 percent of your class is specializing I do not find that number remarkable at all that seems about the typical number for most DO schools. The presence of AOA residencies helps that number as well.
I think AOA residencies in ROADS helps DOs match into these fields because its otherwise uphill to do so at ACGME programs. I was not referring to AOA OMM residencies and fellowships. MDs are not going to be stealing OMM residencies but they might steal AOA ROADs residency spots under the merger, so I think the merger is going to wind up hurting DOs more than helping.