It’s quite the opposite - nothing is impossible; if it keeps coming up over and over, it may move from “we thought we’d never do that” to “well, let’s take a look”.
Note that what makes us reconsider is a wide variety of people requesting something unprompted, spread over a long period of time. “Campaigns” to get attention to a feature get much less weight - if it’s a real problem, we hear about it in individual support requests from people who are unaffiliated with each other, constantly, for months.
A great example is auto-save. We designed the UI to be like a print preview, so saving did not fit. But a nonstop stream of different people posted to Problems & Support and wrote in to support requesting it, we took a “we think we won’t do that” and did it.