Dave - this is not true.
Any USA Shooting affiliated club may hold PTOs which are "sorta" required to enter the National matches.
I do believe that some selection matches may be entered only if you have shot a PTO or in a Selection/National match in the past year. Depends on the match.
In about 18 years of taking shooters and officiating at matches, I've really only encountered a few matches where there was a limited number allowed to enter ... i.e. the top shooters and that was the recent Olympic Trials in the part 2 of the matches where we were limited to the space & dates we had Ft Benning available. Part 1 of the trials always have a wide variety of shooters competing.
Now they won't call or email you (maybe as the NRA did long ago), but all the matches and programs are on their website.
Believe me, here in NM we are happy to see some matches & PTO being held in C.Springs again.
Our JO Qualifier matches are also "PTOs" so our junior shooters have these matches once per year to qualify
As you said .... easier if it's local ... Benning/Anniston/CampPerry are expensive trips for us here.
We are an affiliated club, but do not hold PTOs here as we really don't have enough shooters to do International formats ... those that are, a 5 hour drive to C.Springs is fairly easy