I’ve worked almost entirely in B2B (or B2B2C) software, so I’ve never had the now borderline cliche experience of working on a free application that starts off being exactly what people want, but is unprofitable, and then needs to be made incrementally worse — forever — first just to break even, and then eventually to grow profits ad infinitum.
At least when you just increase your prices, you can try to provide some additional value (as long as it costs less to provide than the size of the price increase) and wave your hands a lot and hope people accept the tradeoff. But with this, Instagram is just… worse. It’s not even debatable — the business makes tons and tons of money doing what it does, but if the product was worse it could make more. So they made it worse.
Writing user communications for this kind of thing seems like it would be absolutely soul-crushing.