[ilstormcloud]

The JWST has an extremely sensitive IR camera. And it is going to cool down to near absolute zero so that the IR sensors don't get flooded with radiation from the rest of the telescope. Because it will get so cold, it is not going to be emitting much IR (I think this is what the GP said when they said "generating"). Your typical deployment observation IR camera's won't be of much help in that case.

[bmitc]

That makes sense, and I got thrown off (by maybe misreading the comment) thinking they meant the camera or something else would generate additional IR to illuminate the telescope, which I got confused by. It makes sense now that the comment was meaning that the cool down was to reduce as much telescope generated IR noise as possible.