How about thinking of "entry level" as something that works for the user to its minimal intent and purpose.

Entry level I think, is dependent on the individual's needs for that bike. I don't think it fair to include prices in the definition of "entry level". So let's say I only ride simple singletrack with no jumps/drops and only a few logs to hop over and not a very topographically interesting terrain, then even the lowest model Iron Horse would do the trick. And to me that would be entry level.

If I'm doing Freeride or something else, then there would be a different "entry level" for that category of riding as well.

And thus using price as a determinant for the whether the bike is "entry level" or not wouldn't work too well. That's my take on the topic.