How long does it usually take for the

[swift steppe]

It depends on your connection speed, but it's typically a few hours not days.

What happens if you reload the chrome://components page (F5, reload button)?

[wind sonnet]

The status is still 'downloading' when I reload and (await ai.languageModel.capabilities()).available; gives 'after-download'

Is there any way to check the progress of the download?