Someone else mentioned as well, but some very specific monopoly/necessity cases could change this delineation, however I could only see this being necessary with a much different environment than we have today (that is, situations without feasible common carrier alternatives, _maybe_ google search would be an example today).
I won't speak to your particular motives because I don't know you from anyone else, but I sometimes wonder if a core driver behind wanting to mess with section 230 is because people feel entitled to an audience at low/no cost to them, at the expense of platform owners, to blather on about whatever they please. To this end, I say "nope, you're not entitled... we have an open internet, drive your own damn traffic".
You mentioned Google Search, I'd add Youtube for video content, Twitch for streaming, FB for social network etc. Sure, you can broadcast video content without Youtube, there's vimeo or you could host it yourself, but it's really not a feasible approach. Much like you don't really have to rely on the local utility company to provide you with electricity and water, you could totally run a generator in your back yard and have trucks bring in fresh and move out waste water ... but it's not a realistic approach.
> To this end, I say "nope, you're not entitled... we have an open internet, drive your own damn traffic".
I'd respond that we don't have an open internet, but more importantly: you don't have to be a platform, nobody is stopping Reddit from being a publisher.
The reason why they don't want to legally be a publisher is simply that their low-cost approach doesn't work if they have more responsibility for what they publish. They very much want to be able to pick and choose what is published, but they don't want to be considered a publisher.