These days announcements like this just make me want to put on my tinfoil hat - what's in it for Google, though? Why make it more convenient for people to submit webpages to you?
everyone elses product does it
gemini is a paid product.
this is google introducing a feature that will encourage more use of a product that they charge money for. we don't need to speculate "how does this benefit google" on the products that they directly charge for.
More Google use, more data they gather, more ads they can show you
If you look at market share, Google the search product barely changed.
In terms of financials, Alphabet is earning more than ever on ads, according to earnings.