On one hand, this had to happen at some point. I feel the split between ChatGPT vs. Codex wasn't helping OpenAI.

Anthropic did it right from the beginning by unifying everything in the same application. From my perspective, Codex is much better than any other app, but for non-technical users they were still stuck in ChatGPT only, and "nobody" knew about Codex. Anthropic also did it better by putting everything under the "Claude" brand: Claude Code, Claude Cowork, etc. Compared to ChatGPT vs Codex. OpenAI seems to be trying to revert that unwanted split.

With that said, I share the sentiment that it's 100% unclear what's the difference between Codex and Work. Chats now are a second-class citizen of the app. Although the "Attach to task" feature of chats looks useful. Putting "Chats" below the "Tasks" section would have been much better.

This may end up badly. Most people use ChatGPT just for regular chats, and they are not used to "agentic" interactions. It may take people time to adapt, and you can definitely lose users during that transition.

This also seems to have indirect implications regarding pricing. Codex (and Work) consume credits. Chats were also limited before, but you could mostly use ChatGPT without thinking about it. Now people will inevitably use Codex/Work more, simply because that's what the UI shows them, thus consuming credits. This will force you to keep an eye on credits a lot more.

Others have mentioned that the old ChatGPT can't be installed any more. Only if you had it installed before, it now became ChatGPT Classic. However, you can still add the chatgpt.com page as a Web App. You'll need an internet connection to use it, but the old ChatGPT app wasn't working properly without internet anyway... so the overall experience may not be that different. I'd even say that, to me, the web UI has always felt more polished than the native app.