I can imagine this happening with large deflation (10%, say), but what about 2% or 1%? It's not obvious to me that people would not buy a TV they really wanted if they knew it would be $392 instead of $400 next year. If consumers actually acted this sensitively toward a drop in prices, then wouldn't nearly all consumers wait for sales for all purchases? But we know that is not the case. Hell, if consumers were this sensitive toward their finances, they certainly wouldn't pay lots of interest on avoidable credit card debt, right?
Also, I think in the real world today, a home would still sell in a deflationary environment, given serious supply shortages. Especially for those buyers which are looking for a home and not an investment (investors would lose long term in a deflationary environment, as you say). Couldn't temporary, modest deflation actually open the housing market up for those "real" buyers primarily looking for a place to live?
So it's pretty reasonable to be concerned about deflation.
Broadly it was a time of sustained growth in both the United States and United Kingdom, despite the deflation which was driven by industrialization and productivity gains. However, certain industries did suffer as a result of the deflation, so it was neither an unvarnished good or bad economic period.
You know what causes a downward spiral? People stop buying things, sales drops, layoffs / cuts, people buy less, etc.
I see companies freak out over 1-2% drops in sales, how is inflation not causing people to drop consumption by 10%? I don't travel, I'm eating out WAY less, I am price/bargain hunting far more. I never buy gas without gas price map checking. I'm holding back on as much purchases as possible. I don't even think about buying any clothes not on sale. Hell, I basically don't buy clothes unless absolutely needed.