You get where i'm coming from generally. What i bolded above is what they miss, and in my experience, what many conservatives miss. My problem with it is that people who didn't go to church (and in some places, didn't go to the right church, like Protestant vs Catholic) felt like outsiders even at that time, and feel that a return to that time means, from a mutually exclusive viewpoint, that it must then mean they aren't wanted or valued members of society, which is what you mention later on.
"Neighborly" values are certainly something that have waned in recent years, but there are a litany of reasons for this happening other than immigration. My point is that many conservatives view immigration as the focal point for why this is the case, when many other reasons (the flight from small towns, the necessity for a two-income household, much longer hours worked, in general, by white collar America, etc) have contributed to why that time is in the past