You couldn’t be more wrong. It’s absolutely possible to get mature 5yo deer to eat at a feeder. You just have to start when those mature deer are yearlings. I have 4.5 yo deer at feeders regularly but those same deer have been eating at feeders for 4 years now.
To say I’m wrong is a little out there. Anything could happen, that’s what makes hunting fun. Playing the odds it won’t happen though. How many 5+ year old bucks did you kill over your feeders last year?
Oldest buck I have killed at a feeder was professionally aged at 7.5 years. I have killed 6 that were over 4.5 in the last few years that were at feeders of that were eating from feed spread in the previous 1-2 hours, and I have seen 40+ bucks over 4.5 years old at feeders, just not deer I was allowed to shoot as a guest on that club.
Again, it's what they get used to seeing/hearing. I do not believe that you would have a good chance killing a 5 year old the first season that a feeder is in operation, but once it has been running for 5+ years, they are used to it. The key is year round operation. I never let mine stop running, just adjust the time down when feed starts to build up.
I have also killed mature bucks within hours of filling a feeder, but it is in areas where they are used to feeders being filled, as well as after using a road feeder on my way to the blind.