From my very limited experience it seems the 1% rule is possible...given time.
Right now with the economy, credit, prices etc. People are not going to pay 1% in desirable and economically stable areas because for that 1% they can buy almost 2x the house vs renting. In fact, in almost ever place in the country that has an influx of people moving too it, economic growth and all around desirable place to live people are buy, hence driving up the prices and making the 1% rule even harder.
Sure you could invest in Lubbock TX, with flat (compared to inflation or national average) economic growth with a huge transient population of about 1/5 - 1/4 being college students and succeed in getting around 1%. But personally due to my investment goals I say F that noise. But that is for my personal reasons. That might be something you have the time, effort, energy, and money to do.
Now at the beginning I said with time everyone can get to 1%. And in Denver and the Springs that is the case. If rents keep going like they are. And we continue to see the growth that we do. The property I bought in 2015 will be at the 1% rule in a few years. And I am ok with that, again due to my financial goals and personal plan.
Personally as a "rule" the 1% rule (and sometimes quoted 2%) is not really realistic, much like the idea of a single income household stopped being realistic for the most part in the 70-80s. It is a hold over from the 2008 bust where you could by a nice huge home for pocket lent and then not even need to rent it out for much to make money. And of course most people didn't have the credit or jobs to get financing to buy a home.
But that is my 2c.