Nobody using it is actually the ideal outcome. AI features are added, at no additional cost to the consumer, to extract money from investors. If customers began using the product, this feature would actually start having an ongoing cost.
Thing with investor money is that after a while the investors start asking where their dividends are at. If you put all that money toward building features nobody asked for, you're in for a rough time.
I suspect it's also a defensive move.
Imagine you make a widely hated product targeted at huge corporations. Workday, Jira, Oracle Financials, anything like that.
Then you find that all your users are using ChatGPT to automate their interactions with your product. Instead of your product being crucial to your customers' business and almost impossible to replace, it's turning into a dumb pipe connecting LLMs - and looking very much threatened.
After all, data lock-in is a core part of your business strategy.
Getting people to use your AI tool, though? That makes your product stickier, and lets you charge more too.