That just made my head spin even more. (Like, I get it, but it's just a very tortuous naming system.) The free version is called Pro, Gemini Advanced is actually Gemini Ultra, the less powerful version upgraded to the more powerful model but the more powerful version is on the less powerful model.
People make fun of OpenAI for not using product names and just calling it "GPT" but at least it's straightforward: 2, 3, 3.5, 4. (On the API side it's a little more complicated since there's "turbo" and "instruct" but that isn't exposed to users, and turbo is basically the default.)
But you don't pay for GPT-4, you pay for a product called ChatGPT Plus, which allows you to write 40 messages to GPT-4 within a three-hour time window, after which you need to switch to 3.5 in the menu.
People make fun of OpenAI for not using product names and just calling it "GPT" but at least it's straightforward: 2, 3, 3.5, 4. (On the API side it's a little more complicated since there's "turbo" and "instruct" but that isn't exposed to users, and turbo is basically the default.)