This is hilarious. "I admit I know nothing, but I'm not gonna let that stand in the way of a wild assumption...:

Not as "wild" as you may think. Railfans are notorious for vastly over-estimating the awareness and appeal of the objects of their affection among the general public. Ditto just about any other similar endeavor and their enthusiasts, from NASCAR to pro arena sports to public libraries and art museums.

There seems to be an attitude by some that these two engines are such a major part of the City of Portland fabric that it is inconceivable that the city would ever let the engines go cold.

The Germans (never a source for wackiness) have a word for this: Schadenfreude
Some people desperately want to declare a person or group (often, one for which they feel envy) ready to call it a day for any reason they can find. We all have seen it countless times here and in any other internet forum.
The 'attitude' stems from seeing what they've done with the funds they have raised, the number of people actively involved and one of the finest new facilities devoted to steam locomotives in the US.
If you ever visited the place and talked with those handling all this, you'll see what the locals know; they have money for all this, or certainly the ways to raise it.
Any group getting ready to install a turntable which is really doesn't need which will sit outside an engine house that is cleaner than most railfan's houses is not in a position where the membership is lying awake at nights worrying that the fires will be dropped for good. Especially not over something as basic as trackwork someone online (who probably never saw it in person) declared has issues.

I'm not all that familiar with Portland but I suspect that 4449 and 700 do not have the local following that many railfans seem to assume. If I took a survey of Portland residents, how many know anything about these locomotives?

The Germans (never a source for wackiness) have a word for this: Schadenfreude
Some people desperately want to declare a person or group (often, one for which they feel envy) ready to call it a day for any reason they can find. We all have seen it countless times here and in any other internet forum.
The 'attitude' stems from seeing what they've done with the funds they have raised, the number of people actively involved and one of the finest new facilities devoted to steam locomotives in the US.
If you ever visited the place and talked with those handling all this, you'll see what the locals know; they have money for all this, or certainly the ways to raise it.
Any group getting ready to install a turntable which is really doesn't need which will sit outside an engine house that is cleaner than most railfan's houses is not in a position where the membership is lying awake at nights worrying that the fires will be dropped for good. Especially not over something as basic as trackwork someone online (who probably never saw it in person) declared has issues.