No changes yet and the naturalization process is generally very easy, 5 years as a permanent resident to qualify (unless married to a U.S. citizen for 3 years, then only 3 years to qualify). USCIS's web site provides very good information about the natz process.

My wife is a non-US citizen (Mexico) but has lived in the US for her entire life as a permanent resident. As in, she was born in a Mexican hospital but was taken directly across the border to her home in the United States when she was released to her parents.

It's my understanding that if she ever decides to pursue citizenship that it's generally easier to go the permanent resident qualification route vs. the marriage route. Is this understanding correct?

As far as I know it is irrelevant. If she is a permanent resident and has lived in the USA for more than 5 years that 's it.

I am confused by your question. Are you sure she is a legal permanent resident ?

Yes, she is a green card holder.

My question is only whether the marriage route to citizenship takes more time, effort and money than the route of permanent residency for 5 years.

Thank you! :)