This is not my thing at all, so this might be a really silly question, but...
Are people who have avoided prescribed antibiotics in a better position than those who haven't? Then, what is the effect on such people of the antibiotics taken in by eating meat from animals which have been give antibiotics? Have the people who have been avoiding completely wasted their time?
It's hard to know the answer to this question.
Yes, antibiotic resistant bacteria pose a new threat to everyone (likely still less of a threat than non resistant bacteria did in 1950), but maybe not equally.
it's possible that antibiotic-resistant bacteria have more chance to take hold (asymptomatically/latently) in people who are regularly exposed to antibiotics.
You could be carrying around MRSA but you wouldn't observe symptoms unless/until you are otherwise in a critical state - wounded or immune-suppressed.
It's not currently obvious how antibiotic-resistance spreads in the wild and so it's still plausible that avoiding antibiotics gives you some degree of protection.
Even if you've never taken antibiotics, you're in the same boat as everyone else. The resistant bacteria are in the environment.
If your immune system works fine, there's less to worry about. The most urgent danger is to the very young, old, or immunocompromised because of illness or therapy. (That said, MRSA infections do happen in otherwise healthy people from time to time)
If you've been avoiding meat raised with antibiotics, you're part of the solution, because you're pushing the market away from the cheap short-term fix (antibiotics) towards more sustainable solutions without the societal consequences.
The problem as I understand it is not with human immunity, but rather that we will not be able to kill or control the bacteria when it's bad enough to warrant treatment. I'm not a biologist, but I'd wager the answer is that they are not any better off.
Are people who have avoided prescribed antibiotics in a better position than those who haven't? Then, what is the effect on such people of the antibiotics taken in by eating meat from animals which have been give antibiotics? Have the people who have been avoiding completely wasted their time?