UI changes and new features aside, the web is just so much more adversarial nowadays. It's no wonder so much rubbish floats to the top of Google because the reality it's drowning out all the other content.
If you had the source code for 2005 Google it would be objectively worse today than it was then.
Just be prepared: the future of the internet is navigating politics. You better be prepared for people to be upset at query X returns results too right/left/up/down for their political preferences. Then senators start tweeting at you.
Also, my search engine will be called "Jays Favorite Websites" and the right side of politics can bite me.
I'm trying to think of any changes to Wikipedia that happened after it launched and can't think of any. It surely does its job, but it doesn't change and there is no drive. Wiki concept was novel at the time, they did and continue to do an amazing job, but there's no evolution there. Or maybe I'm just a blind or unaware or biased - but, honestly, I tried to think of something and nothing came to mind.
Google constantly tries out some new things. They're really bad at maintaining them, they can't stop inventing chat services, they suck a lot and we could bash them endlessly, but let's credit what's due - they're always exploring some frontiers.
Just because cars still mostly have 4 wheels doesn't mean automotive engineers haven't been innovating the past 100 years.
The world would be a better place if google search had been made a not-for-profit (maybe like wikipedia?)
By this point I would (maybe) pay a monthly subscription for a really good websearch like google circa 2005-2010