In the interest of clearly communicating:

I used "fuel" in the meaning "to make people's ideas or feelings stronger, or to make a situation worse", not "a substance that is burned to provide heat or power", see https://dictionary.cambridge.org/dictionary/learner-english/...

I did provide two quick examples of these effects happening in the absence of ZIRP, so it is clearly not always required.

As, sadly, is not a tank of gasoline or ill intent to set a house on fire - these things can happen by accident, often a single spark is enough.

There's plenty of literal fuel beside gasoline, and there's plenty of "startup growth at all costs" fuel beside ZIRP.