I haven't read this entire thread yet, but am presently camped in the midst of quite a few friends who absolutely love Mexico, me included, who do not go back after having done the winter trips for years, myself for seven winters. From Canada, we escape from various weather related realities (we on BC's southern coast, from the dreaded November fog and December's notorious rains) and we have found life quite fine in Southern California and Arizona. We're having a reunion and Christmas Dinner here that serves to replicate what we did on a beach in Mexico the last time four or five years ago. We've done this for four years. Nearly all to attend have arrived here in southern California already, and this year's is the largest contingent we've had.
After Mexico, when we first came camping RV style to the American southwest we visited Senators Wash, 30 miles out of Yuma, where we were told that at one time 4,500 rigs came in a season to camp there. That was years ago and the numbers for our first visit and the next year we visited, were nowhere near that. With some of the older RV'ers there then, the CB Radio was still very much in vogue.
Nowadays we find several other places to go, and other things to do. They include Cactus League Spring Baseball Training, NHL Hockey in Phoenix or L.A., car racing, maybe some desert golf, rock hounding, and populating several desert BLM lands, some to be kept secret from "the masses." There is much to do.
So why are we here, and not in Mexico?
We're happier here in USA. The expense of quotas and fuel has risen too fast. The paperwork to satisfy Mexico has always been onerous, maybe more so now that deposits must be made for a vehicle; the understanding that the laws are so different and considered unreliably enforced; escalating RV fees, often because electric rates are so high; a general perception that personal security can be too easily compromised - that there is a lack of policing, and too many weapons now in the wrong hands. We have heard, first hand sometimes, of dangerous incidents, stolen vehicles and items.
To be honest, in a year and a half being in Mexico, 20 K driving a motorhome there, we have been very uncomfortable with our situation only two or three times. We love the people. But we know the Mexican society is not always the easy going one of the north, many people are too desperate to get ahead. (Please, just not mine!) My DW would never drive there again. We've read the stories. Mexico is no longer the bargain it once was.