The WWW has never been a high-trust place. Some smaller communities, sure, but anyone has always been able to write basically what they want on the internet, true or false, as long as it is not illegal in the country hosting it, which is close to nothing in the US.

The difference is that there historically weren't much to be gained by annoying or misleading people on the internet, so trolling is mainly motivated by personal satisfaction. Two things changed since then: (1) most people now use the internet as the primary information source, and (2) the cost of creating bullshit has fallen precipitously.

I agree. It's not that the web was high-trust. It was more that if you landed on a niche web page, you knew whoever put it together probably had at least a little expertise (and care) since it wouldn't be worth writing about something that very few people would find and read anyway. Now that it's super cheap to produce niche content, even if very few people find a page, it's "worth it" to produce said garbage as it gives you some easy SEO for very little time investment.

The motivation for content online has changed over the last 20 years from people wanting to share things they're interested in to one where the primary goal is to collect eyeballs to make a profit in some way.