I have a rhetorical question, will the bugs die back at some point to an acceptable level or are the survivors treated for life with a regimen of $ and the minute the funds run out certain death ? My guess is latter as one bug is pretty much unacceptable right ?
I know you said rhetorical...have you dealt with EAB? It is a VERY aggressive pest. There are very few untreated trees that are still alive and millions upon millions of untreated trees that died in a 4-5 year period. I didn't make up the insects' biology, I just offer options including telling how the tree themselves or letting the tree go where it is not critical to the landscape. Had a client that wanted me to treat all of his ash trees. I pointed to one in a group of maples: "would you miss that one if it dies?" "No". We didn't treat it.
I have told every client "plan on treating at this level for perpetuity. Hopefully as there are fewer live host trees we can scale back treatment...but I want to make those decisions based on research which may be hard to come by. Are you willing to treat your tree for 10 years then be the 'control' where we quit treating the tree and see what happens?"
I'd be open to other IPM options and use them on many other trees...I agree that we don't want to inject every tree in America. However, I haven't heard of a viable alternative to insecticides to stop EAB from killing ash trees.