Sadly I believe you are correct. The worst part is being ugly and awkward would make research heavy programs more attractive but all the places with great research are also the places that have prestige and fill with beautiful outgoing AOA types.
I'm a terrible actor and for programs I know I'm ranking 6-15 its hard to pretend "I really want to go here" and its getting even harder as the season drags on.
As others have said, interviews in general don't hold that much weight. In general, there is a rubrik with a bunch of things like clinical grades, USMLE step 1, interview, LORs, research, etc
Each category can be assigned a value (i.e. 1-5, 1=poor, 5=outstanding ... step 1 > 260 may = 5, >245 4, >230 = 3, etc ... all honors = 5).
Most interviewees will get 3s and 4s for the interview... a few will get 5s and 1s. Then a weight will be applied to each category. Usually Step 1 and 3rd year clinical grades ratings will multiplied by a value of say 1.5 (so if you got a 5 for step 1 it will become 7.5). Things like research and LORs multipled by 1.25. School rank by say 1.1. The interview will probably be less important and not multipled by any number. If you are AOA, they may give you say an extra 3 points. These numbers are all approximate.
These values for each applicant are added together in excel and applicants are ranked by their total score. Rank may be adjusted based on subjective factors listed below. People with a score of above X are offerred an interview (or the top 100 are interviewed). Certain schools also require other things like AOA status and/or step 1 > 240 plus a score above X. Others offer auto-interviews for people who rotated there or applicants from the local med school.
After the interview and after the interviews have been scored and the rank list adjusted accordingly, the PD, chiefs, committee, etc will discuss the list and certain candidates may be moved up, down, or off the list (based on subjective factors such as the interview (aside from the score), if someone knows/is friends with/respects the LOR writer, if the applicant is related to an attending at the institution, if you rotated at or if they feel you expressed genuine interest in the program or geographic location, etc).
So in the end the interviews usually doesn't hold much weight- how much more can you really impress them in 15 minutes? And usually the interview is only a single point value in the rubrik that is not weighted that heavily. For most, the interview won't matter. However, if you come off as a nutjob there is the potential that they will throw you off or put you at the bottom of the rank list. A lot of applicants will look very similar on paper even after all of this is done. So quite often, if the people on the committee know or remember you, they may boost you ahead of someone who is close to you on the list that they don't remember. Some places will auto rank applicants from the associated med school at the top providing they meet a minimal criteria.