However, when at the Grand canyon in Arizona, it seems that DST does get followed. This makes it difficult if you happen, like I did, to do a trip the weekend of DST shift where you start in Phoenix, AZ, go to the Grand canyon, then proceed west into a different time zone.

There's a funny thing about "mistakes" in language. The more common they are, the less they're mistakes.

I copied what the article said – when in Rome do as Romans do.

Actually, the correct way to write it is "Daylight-Saving Time" [0]. I strongly suspect that had it been commonly written this way from the beginning, people would have understood how the phrase is constructed -- it means, the time that saves daylight -- and the whole "daylight savings" thing would never have gotten started. Consider that the hyphenated form also suggests a different pronunciation, with the primary stress on "day" and secondary stress on "sav", rather than the other way around which is how most people pronounce it.

[0] https://en.wikipedia.org/wiki/Hyphen#Compound_modifiers