Because I'm old and was of an age to be sentient when the Prequels were released, I can tell you that, until The Clone Wars was released and redeemed the series, the hatred for the Prequels was incandescent and pervasive and much worse than the hatred for the Sequels, although the Sequels (IMO) are much worse.
You have to understand, the Prequels were not "nerdy" when they began releasing in 1999. They were as mainstream as Jurassic Park or Titanic. Everyone watched them. You would be made fun of if you didn't, actually. Back then, we had a distinct monoculture, where everyone was expected to know of certain things. We did not have the fragmentation of the market into niches or gatekept streaming services. The Prequels were absolutely one of those things. Picture the cultural event of the Barbie movie, except ten-fold.
The Phantom Menace was released in 1999. The hype was absolutely massive. However, this was then met with almost uniform backlash. Most people, even famous standups or talk show hosts, were making fun of how incredibly annoying Jar Jar Binks and young Anakin were. This was extremely mainstream, it was not consigned to just fans. While the podracing and Obi-Wan's duel with Darth Maul were praised, the rest of the movie was considered childish, with stupid dialogue, and bad CGI. While Ewan McGregor, Liam Neeson, and Natalie Portman were sparred, the voice actor for Jar Jar, Ahmed Best, and the child who played Anakin, Jake Lloyd, faced such severe harassment that they later admitted in a documentary to suffering severe, long-landing mental health issues.
Attack of the Clones came out in 2002, and this was was considered not as childish as the Phantom Menace, but still very stupid. Everyone harassed Hayden Christensen for his wooden dialogue. The cultural consensus was that he was a pretty boy that lacked talent. This took its toll, as after the Prequel series, Christensen left mainstream Hollywood entirely. People really started concluding, around this time, that Lucas himself was to blame for how bad the Prequels were, citing the incredibly unconvincing romance between Padme and Anakin, and the ridiculousness of the dialogue in those scenes. However, Ewan McGregor remained very popular, Natalie Portman grew in popularity, and the key action scenes (e.g., Kenobi versus Fett, Yoda versus Dooku, and the Battle Of Geonosis sequence) were praised. Outside of the action scenes, people still criticized the CGI.
Revenge of the Sith is what this sequence was from, and it came out in 2005. This was, far and beyond, the most well-received of the Prequels. People liked the dark tone, increased action, and how it finally linked the Prequels to the Original trilogy. However, Padme's death sequence was the subject of mainstream and late night talk show ridicule, and people still noted Christensen's poor performance, melodrama, and stilted dialogue. There were some slap fights among fans whether this was on par with any installment of the Original trilogy, with people who had spent the last six years despising the Prequels extremely loud and insistent that it was still unredeemable garbage.
None of these movies were at all safe to admit that you liked until The Clone Wars, nostalgia, and the poor quality of the Sequels redeemed them in retrospect. However, what is interesting is that the action sequences in the Prequels were always its strongest point, and most reasonable haters could admit that they were quite good. In contrast, the action sequences in the Sequels were always noted to be lackluster in comparison, and were criticized at release.
However, the Sequel hate did not reach anything like the volume of the Prequel hate. Even The Last Jedi, the most controversial installment, was criticized only in niche circles. It wasn't the topic of mainstream jokes. When The Rise of Skywalker bombed, we all collectively winced and agreed it was bad, and moved on. There was little of the overwhelming monoculture discourse that accompanied the Prequels. Remember, the Prequels were released at a time when the monoculture was relentless in immiserating pop stars it deemed fair game. That dynamic of the culture no longer existed by 2015.