Once they price operators out I won't be able to try out new machines for a few bucks. I would never buy a $9+K machine unless I got a few games in first. If I can't test drive I ain't buying, as simple as that.
Add in the sub par quality of many new games (code,ghosting, poor workmanship, bad optos, lack of support,...) and manufacturers will soon find the price ceiling for their products.

The new machine usually has 5 people waiting in line to get a single game in. Some folks are so rude they monopolize the machine for hours. Hopeless.

I certainly hope you are wrong but deep down I am afraid you're right. Very few kids get into pinball or anything other than video games.
My friend's 15 year old wants to be a Marine because he likes playing "Call of Duty", no joke. Same guy got sore legs after we went hiking 3 miles. The youth ain't what it used to be.