So you could say 1800-2000M you would consider a short runway then.
Reason I ask is, that you could be flying along and you needed to divert into an airport. Lets say your unfamiliar with the area, so choosing a suitable airport could be difficult. If for example, I saw a runway at 1900M and its suitable for passengers and operations but there is another airport 30mins down the road at 2400M but I needed to land now due to whatever reason it may be.
If I had a rough ball park figure in my head, I could say no that airport is not suitable with such a short runway.
I wouldn't choose to land at Cranfield (EGTC) in any occasion unless I was falling out of the sky due to the runway being rather short.