Your Ace Trainer Badge
Answers
I was in a similar situation, the entire region overrun by constant hoards of red and yellow players. I could literally go a month or two at a time without encountering a single gym that was already blue.
Fortunately, I had a habit of prestiging against myself at least once every time I took a gym, to make it so any attacker would at least have to fight me twice to kick me back out, to try to buy an extra minute or two. Sometimes I even did it dozens of times to bump the gym up to level 7 or so, to see if any other blue players would ever appear to claim any of the spots I opened up. So by the time the gym system changed, my Ace Trainer badge was at 1413, and I'd estimate about 90% of that was from prestiging against myself.
By a little
I wasnt much of a battle person, i didn't care about pokecoins neither through gym or cash, i was the kind of person that would only defend a gym if there was that old 2 initial slots, until i realize that my bag was always full, so i started battle, when i saw that i was close to reaching gold i started focusing on battle girl and ace trainer, that 1001 training was 3 days before the rework.
"Only" 1801 on my trainer badge. Training was fun and made quite a lot of mid-list pokemon useful. But it was already dead in my area when they changed the system. All stagnant gyms with uniform defenders, which nobody bothered to attack, as they were inevitably taken back within hours and restacked with exactly the same defenders. And as the defenders were always the same type and strength, in the end it was always the same prestigers, too, with neither thought nor strategy left.