Trying to pitch the Fediverse on its technology backend to non-technical people is a bad approach, but so is trying to pitch it in terms of digital detox or "better" culture.
The backend is for the tech people, and the rest is your regular messy people. There are as many good pockets of the Fediverse as bad, because that's the internet.
In light of that, it's questionable to what extent the Fediverse should be pitched as a distinct thing in a similar vein as those platforms some Fediverse software emulates. Fediverse, open social web, whatever you want to call it is of main relevance more to those working on it and trying to promote it among developers.
To those of us using these platforms, it's probably better to simply invite those to our respective instances/sites as simply another site/app without all the jargon and background.
Forget Lemmy/Mastodon/Pixelfed/etc. except insofar as it's in the URL or needed to search apps. Ultimately they're backends, and many weren't going around inviting people to their sites or enthusiast forums talking up apache or phpbb or the like.
The Fediverse is an emerging subset of the open web with improved interconnectedness, and so what's more important than it is reinvigorating the spirit of the open web by reminding people there's more beyond the closed web by inviting and encouraging them to visit our open spaces alongside their own. It's closed web/walled garden thinking to discourage visiting a variety of sites and using a variety of apps.
The open web thrives, enduring, enveloping and eroding the enclosures despite their efforts to ward off its persistent being.
TL;DR:
Invite people to these spaces without the technobabble, don't give them shit for visiting/using enclosed sites/apps.
Celebrate the open web by showing them more places online to check out alongside theirs.
I've been arguing for over 2 years now that the actual value proposition of the fediverse is Community+. There are several Lemmy and Mastodon instances that are built around this -- tenforward.social is a Star Trek themed and focused Mastodon site, where the vast majority of local chatter is focused on Star Trek, and startrek.website, beehaw.org, midwest.social, ttrpg.network, etc. are all community or interest focused Lemmy-based websites -- and they all seem to actually work in that model. People aren't signing up to the Star Trek Lemmy site to talk primarily about Call of Duty or American politics. They get their Star Trek community, and they can engage in those general interest discussions that are being hosted elsewhere, and everybody wins.
The key to growth, then, really is getting enough special interest and community websites up and running on the fediverse, and letting people discover the the power of being connected to people on other social media websites without having to sign up over there, too.
If Bluesky was using ActivityPub, there'd be no issue here right now. We'd all be able to get Community+Bluesky and be all the happier for it. But they've created their own system that's prohibitively expensive for the average person to utilize without having a direct connection to Bluesky's hardware, meaning the control forever remains in the hands of corporate interests and the rich. And that's just a play at being the next Amazon. We're either locked out, or we're under their thumb. And that's not really where any of us who are engaged with this fediverse project wanted to be.