Why now?

I mean, they certainly know that introducing ads with be a huge motivation for consumers to seek other options.

The primary differentiator of OpenAI is first mover advantage; the product itself is not particularly unique anymore.

IMHO consumers will quickly realize that switching to an alternative AI provider is easy and probably fun.

This seems premature to give up their moat in the name of revenue. Are they feeling real financial pressure all of the sudden? Maybe I'm missing something. Looks like a big win for Google and Anthropic.