A small team and an llm will tackle search?

They will run into many problems. The Google brand for search, the inability to index most of the web as a new crawler, the lack of the top browser, your own mobile OS, default search placement deals with everyone. And that doesn't even look at the technical issues, scaling or the lack of a business model to pay for it.

You could build your own Google drive many have from dropbox to mega or onedrive. Doc suite is possible but harder then you think.

LLMs were invented by people working at Google. LLMs won't kill Google it will offer them a new profit center.