This is no different the open source/free software. Just because you created some software, and it became popular, and a large contributing community, and you started 1% of the value, does not mean you either created most of the value, or get to extract it. Attempts to do so basically always fail.
The argument that it would not have happened without you is almost always wrong - it is almost always a mistake to assume success is simply because of your choices, and not lots of factors. This is one reason repeat success is very very very rare.
I'm not saying they have no legal right to try - of course they do. I'm just saying it doesn't work because nobody thinks they should be allowed to let it work.
How they run the site and whether they need to make a profit is of no consequence to users - they don't give a shit. You can't make them give a shit. It wasn't who they attracted. They don't have a 100 million users who want them to make a profit. They have 100 million users who don't give the slightest crap about whether they make any money at all.
Yes, trying to generate profit on value they don't create is freeloading. Quite literally, in fact. It is the literal definition of freeloading to try to extract value by taking advantage of what others do. You don't argue they create the value, but instead because they own the platform they are allowed to extract it.
Legally, yes. But that's sort of irrelevant. Socially, no.
The crux of your argument is basically "if my ideology is right than investors are dumb and this is a bad investment"
I would agree with that. It was always a bad investment. It still is!
Precisely because freeloading of the kind they are doing always generates enough ire over time to ruin the community. Usually before you can extract enough profit to be worth it.
You can feel sorry for platforms, and for me, that's okay. But you still haven't shown that i'm actually wrong, and in fact, what i've said is backed up by the consistent failure of things that operate the way you seem to think is okay.
I mostly feel sad for you. You seem to have forgotten somewhere along the line that corporations as a kind of entity were created to serve society (not investors), and not the other way around.
I'm not saying all things this large should be non-profit, mind you, just that the kind of skimming that reddit is trying to do, where they think they can make a few bucks in profit per user through freeloading, while providing nothing in return, is neither helpful to society, and doesn't work anyway!
There are more symbiotic for-profits that realize they need their communities to want them to succeed, and do okay.
Put another way - for profits running hosting like Reddit where they think their profit is more important than the communities, and that they are the reason for the success of those communities, basically always fail.
Those smart enough to realize neither of these are true sometimes can make a go of it.