There's a lot of talk about Niklas Luhmann's method of zettelkasten, but what about the 500 years of the related practice that was also highly productive?
Based on experience with Pingbacks, the Webmention specification requires the sending site to have a mentioning URL on a publicly available web page. This requirement by itself cuts down significantly on spam as it increases the cost of sending it. (Pingbacks/Trackbacks didn't have this requirement so it was easy to programmatically spew spam in all directions.) In addition to this, there's no requirement to show the received Webmention, so there's less benefit to some spammers in these cases.
Many people who do receive and display them have separate mechanisms to moderate them before display, which also tends to minimize spam. Other sites that support Webmentions also dovetail with anti-spam services like Akismet which can help filter out spam out as well.
And this is all without anyone adding the Vouch extension to the Webmention spec.
Keep in mind that webmention.io is just a third party service to allow sites to use and leverage Webmention notifications without needing to write any code. Many major CMSes like WordPress, Drupal, Craft, WithKnown, et al. either support the spec out of the box or with plugins/modules. Each of these can also leverage anti-spam methods they have available separately. As an example of this, the WordPress plugin has an allow list for automatically approving webmentions from sites one regularly communicates with.
The idea of Webmentions has been around for almost a decade, and the spec has been a W3C recommendation since 2017. Only one suspected case of Webmention spam has been reported in the wild in that time. I'd conservatively estimate that with 10,000+ independent websites sending/receiving over 2 million Webmentions in the past several years, it's not a bad start. For more details, ideas, and brainstorming for your potential use-cases see also: https://indieweb.org/spam
https://huffduffer.com/ is another good discovery/bookmarking tool for podcasts. It has RSS feeds for everything on the site including custom searches that could potentially pick up your favorite contributors. The bookmarking functionality also makes it easy for you to quickly add things you find to one or more followable feeds for the one-off guest appearances you may hear about.
(Originally posted at boffosocko.com/2020/03/21/55769517/)
Here's a list of several including an "IndieWeb Ring" that was started in the last two years that features personal websites: https://indieweb.org/webring
I think they turned off the free sites/hosting a year or two ago, but the opensource project is still around and doing well. It's not hard to spin up an instance with the opensource software and I think there are still a few hosts like Reclaim Hosting that offer one button installs of it.
It's "federated" in that it runs on simple web standards and protocols. You can use almost any CMS or platform out there and pipe your RSS,ATOM,JSON, or other feeds into it. If your site supports the Webmention protocol, then any comments made by other micro.blog users will come back to your original post where you can choose to display them (or not). https://indieweb.org/Micro.blog may give you some additional ideas/help.
Micro.blog is exactly just this sort of hybrid solution. If you start typing a short status update you can publish it as such. Once you go past the 280ish character limit, micro.blog gives you a new field to give the post a title (if you want).
I use my personal website running WordPress a lot like this hybrid model as well. I can do all the things you mentioned and have separate feeds for all of the related post types (articles, status updates, photos, embedded media, etc.) Micro.blog also allow me to pipe my RSS feed into it so that I can interact with people there and any comments people make within micro.blog come back to my original post where I can see and reply to them.
Perhaps I'm missing some context in the thread, but it seems like many are missing the fact that Micro.blog is actually trying to solve just this--you own your own domain and the data! It is one of the first paid IndieWeb platforms out there that is trying to make it simple for the non-technical user to jump in with both feet. While it may not have _everything_ yet, for a relatively inexpensive hosting fee you've got your own website for long posts, short notes, photos, etc. that is part of an integrated community. If you want to pull up stakes, you can export your data and move your domain and site somewhere else.
It also seems like a major bonus that it also supports new specs like webmention, micropub, microsub, etc.