Sometimes statistics number do not match the real-life situations. Do you ever wonder why only 3 students apply to ortho in the first place out of many hsps recipients. Not to mention Army pays you 50-60k extra for ortho specialty (AEGD gains extra pay too though not a specialty) Plus, Army branch do not ever let you apply to civilian specialty.
I have read real posts of army dentists serving and graduating and they share that they did not even apply because their chance is slim. Unless you are a super star and can outcompete your peers, yes you will get in. But this does not make specialty residence any easier than civilian. OMFS is something that the Army branch needs (my post only says ortho specialty for military) but 4 year of dental school pay back + 6 year of OMFS pay back = 10 year pay back on top of 10 year you spend in school (4 year dental school + 6 year OMFS specialty). Additionally, when someone spends 10 year in military and only 10 year away from earning full retirement and pension, they feel inclined to do so BUT some people just don't want to spend a career in Army dentistry.
I am not misinforming and exaggerating. Go read on some more specializations as an army (ortho, period, prostho) the link you posted includes the positive vibe and hope for specialization.
On the side note: i am applying for Army HSPS and rooting that i will get it. However, although i like specialization, i won't set my hope high and feel disappointed when I don't get it. AEGD is still good for me.