> quality,

All LLMs are actually converging to about the same LLM, since they are trained on the same Internet/book/average-human-knowledge.

> habit

Habit matter for things people don't pay for. If a person pays, they'll go out of their way to get something for less. Microsoft's big thing is making sure end users never pay for Windows.

> integration,

Not going to matter. Every "AI application" is basically just a prompt and users can make their own prompts.

> hardware investment,

OpenAI doesn't even have a hardware investment, just a deal to use MS Azure. Other AI companies can and will just a cloud too.

> their interface,

Every LLM has the same interface. A chat window.

> their brand"

As above, brand matters for either habit (which again, only matters when thing cheap or free), social signaling (which a LLM choice won't give you) or actual differences in quality (which LLMs don't have).