But, fortunately, disabling auto-playing in Firefox is actually not that hard. about:config, then set "media.autoplay.enabled" to false. Done.
or you could just use uMatrix and whitelist sites where you want video to play
https://addons.mozilla.org/en-US/firefox/addon/disable-autop...
When I encounter interesting articles on such anti-user sites, I don't bother browsing the site, I use a script to extract the article and rehost it on a public pastebin. I'd rather avoid them at all, and that wouldn't even be necessary if everyone used atom/rss feeds.
see example for this one: https://0x1a4.1337.cx/o_27/
You can blacklist bloomberg.com & co from your browser with extensions such as https://addons.mozilla.org/en-US/firefox/addon/blocksite/
I'd understand if they ask not to rehost their content tho.