The reason it may be more difficult today is because we've lost a lot of that. Some of it because of modern JS frameworks, but some also because publishers simply don't want to make it easy for the useful stuff to be scraped and extracted easily.
I'm not convinced that's changing because of AI agents (it's getting worse in many ways with anti-agent rules). Maybe improving for documentation pages intended for agents. But if it is changing, I think it'd be far easier to improve the HTML and let the agent take care of the rest.
I've been enjoying https://defuddle.md since learning about it. Works great. Not affiliated.
Most harnesses have a "zero config" plugin that works, eg: https://pi.dev/packages/pi-exa
(no affiliation to either)