> Could we change that culture?

In short? No. You probably can't.

I hate being so blunt because I love the ideas you're proposing and have advocate for many similar things when I was still pursuing an academic career and now from outside of it (albeit in a scientific community where there is a very blurred line except for institutional affiliations).

But you're not addressing the fundamental problem: there's such an over-saturation of PhDs and so few tenure-track positions in so many fields that there is one and only one objective for an early-career researcher: publish, publish, publish. That's how you build the portfolio to get called back for campus interviews for professorships; that's how you build your network and slide into funded grants before building your own, with connections to the program office or review committee that will help you get said grant funded. Although there are many worthwhile activities for an early career researcher to engage in (and, thankfully, a slowly growing recognition of the value of these activities, such as open source development and data curation), only a small subset of them feed into the ultimate goal: a tenured professorship.

The critical shortage of reviewers these days, at least in my field, is partly due to social dynamics since the pandemic, but also very critically due to the perceived lack of value that serving as a review provides while you're in the heat of the rat race. It doesn't sound like your a practicing research scientist (meaning: you work in a job where producing research and publishing on this content is a primary metric against which your success is measured), but you should really talk to some across a diversity of fields. It takes a _lot_ of effort to provide a useful review. Effort that instead could be funneled into ones own research, for greater impact on your career. And if you're the author of a good paper, you don't need the other reviewers to "help" you with the process. It can be tedious and annoying sometimes, but hell - what difference dos it make if _one_ of your papers is getting held up, you've got 6 others ready to go by the end of the year, right?

The problem is that it's not a "culture" issue. It's the fundamental practice of the modern scientific enterprise. The incentive structures are highly warped - a problem that many of us run into time and time again when we try to push through open science and reproducible science initiatives (and I'd definitely classify your effort in that group). When the fundamental practice and institutions change, the culture will change.

If you'd be willing to bend and constrain your idea to more of a "Reddit of peer-reviewed literature" and focus on expert intersectional communities like ScienceBlogs, you might have something really novel here. There's a ton of value in the open-sourced curation mechanism. I've been involved heavily with /r/science in the past, and while the ecosystem of sub-reddits surrounding it definitely do a good job of "curating" science, it's not really the same thing as what you're proposing. It's a definite niche would could have a lot of value.

But don't expect a lot of scientists to buy-in when you're not offering them anything in return. And again, to make this very, very clear: if your project doesn't help an academic get tenure, I don't see why they'd participate.