I never used the ATM until the last two years or so when I got direct deposit. Now I always get my cash from the ATM, and since it's just $20s that means I never even see $50s or $100s and thus I never get $20s in change either. In the old days when I still got money from the bank, there was one memorable time when I got a 1934 $20 from a bank teller, but I haven't seen an old bill in years. I always look when I get change but its mostly 2006s, and I've never seen an old bill from an ATM. Do the ATMs ever give out older bills?
From the bank ATM's I get new money (the high majority of the times) but from independent ATM's, which are loaded by the location owners, you have a chance of getting a mix of circulated. We have one at work that we load ourselves and we just use money intended for deposits to fill the machine.
I once read a report where an ATM was giving out series 1928 FRN's in pretty good shape. The customer was frustrated when he reached his daily limit. He tried to convince the bank to give him more, but they would not.