Will grammar errors become correct after enough people use them for enough time?

First let me state the obvious—based on my own experience—that hordes of people are confused about certain basic grammar principles. For example, I so often see mistakes in choosing the pronoun to use with direct objects, especially when introduced by and with another person, as in “Joe talked about the book with Anna and [I/me].” Another one is the near 100% usage of “lay” instead of “lie” (and “laid” instead of “lay”) nowadays, even in published sci-fi books that most certainly had professional editors proofread them.

Do you see these kinds of changes as predictors of the future? Will they become correct after enough people have used them long enough? Both of these problems drive me bonkers, and I fight my own little battle against them when possible.

I know that dictionaries are descriptive rather than prescriptive. They’re technically history books. But grammar and style books seem less so, to me. Those seem as though they ought to be prescriptive in order to reduce the erosion of structured and meaningful language.

In this tension between “what people are doing” and “what people should be doing,” are we doomed to forever bear these errors just because too many people don’t know the proper way? Is it worth fighting against them? Do I capitulate to the people who are quick to accept any mass public usage as a fait accompli?

Update

I don’t imagine for a second that my own writing is error free. The difference with me is that when I do learn I have something wrong in my mind, I immediately change once I clearly understand it.

I also am not imagining that language is static or ignorant that today’s correctness is all too often yesterday’s error. The whole point of my question here, then, is: is there value in slowing the change, and if so, how is that done and how effectively?

Another way to look at what I’m trying to ask is that in a way I am hoping to define the limits of pedantry. If being pedantic is slavish adherence to outdated rules in the face of actual and foregone changed reality, then when do we conclude that a change is a foregone conclusion?

Poking fun at my own errors to highlight supposed pedantry on my part is to miss everything I am trying to say.

Update 2

It may not be an easy question, but since language change actually does or does not happen, and every person acts with more or less intention in regards to language change, there must be an answer. What I wanted to explore is the value in efforts to teach the “proper way” vs. the opposite end of the spectrum where any new usage is not just accepted but welcome or even sought out. You know, I’m reminded of something: the conservative/liberal scale:

   |------+------+------+------+------+------|
radical              moderate             radical
liberal                                 conservative

The funny thing about those at the ends of the spectrum is that they both want things to change. The radical liberal wants language to change to something new quickly, just for the sake of newness or evolution or some other not-necessarily-realistic ideal. Similarly, the radical conservative wants things to change just as much, but back to the way it used to be, just for the sake of sameness or continuity or some other just-as-not-necessarily-realistic ideal.

I’m not particularly asking where we should be on this scale as that’s purely subjective. I’m trying to ask about something purely practical and real-world: what is actually effective? Is language change inevitable, and how fast? Are efforts to reduce its rapid morphing either effective or worthwhile in any measure? All these things considered, what position with respect to language evolution is livable, practical, and sensible?

Feel free to edit my grammar. No comment necessary.

Update 3

Something that may be of interest to both my supporters and detractors: this ‘Kinetic Typography’ video by Stephen Fry. I enjoyed it. I don’t disagree with him, but I am not sure I am wholehearted in this lack of disagreement.