And if we get to such future, it's possible that we won't even need a Mastodon/Twitter account to have a timeline. iOS and Android could build native support for following accounts and displaying timelines in the operating system.
I want to be able to have a fediverse feed that's as much RSS feed as news feed, but that's my preference. I'm really glad WP is making it easy for folks to use ActivityPub.
Also, the brand is in really bad shape. Super outdated and stale. I know a lot of people wish it didn't, but that kind of thing really matters when you're trying to get lots of people to think your product is worth investing time into.
Bluesky insists on building its own protocol and is making empty promises (https://atproto.com/specs/atp#future-work) to turn it over to the IETF or W3C at some undetermined date.
In an ActivityPub world, this is particularly unlikely to happen. Arguably, we've actually had a social media ecosystem a bit like this before; there was a time when Wordpress (self-hosted or service), MovableType and a few others could interact via things like pingbacks (a sort of early quote-tweet).
Twitter and Mastodon are cognitively low-maintenance tools. The authoring is very simple, and designed to be within 280/500 characters. Wordpress is the opposite. The UI assumes you're there to write, not view other people's sites and comment on them.
Automattic owns Tumblr, and that type of UI is probably what would get people thinking of posts as "tweet-length info" instead of full-on blog posts.
"Your WordPress blog can now become a profile for the fediverse. This means your readers can follow you and receive all the latest posts from your blog directly on their preferred platform. More so, they can engage in enriching conversations by replying to your posts, with their replies reflecting as comments on your blog post, creating a synchronized and interactive experience."