Threads are supported on Matrix as of a week or two ago. They're no longer in beta as far as I can tell. I don't know for sure how well alternative clients support them, but desktop and mobile versions of Element do threads just fine.
Alternatives (Fluffychat, for example) are usually a while behind Element because of manpower. For example, native polls are in Element but not in Fluffychat yet. So, if you want to risk the transition, best to recommend the official clients first.
That said, I don't know how well threads will actually work in a family context. I like them as a concept, but outside Google Chat (where every message in a room is a response to or the start of a thread) I haven't seen them get picked up naturally.
Threaded messages arguably allow for less fragmentation into other channels / DMs, and they have the checkbox for a particularly important message to be sent to both the thread and main convo.
I'm a thread fan from the start, and I've observed many who were initially skeptical start using them heavily
Maybe we have different teams configs, it definitely has threads. Chats do not have threading, but teams/channels only have threads. At least on our install.
I would rather put my money on not threaded well. The application thread seems to get blocked whenever it's chugging on something important, which locks up the UI.
I forgot, Google+ is killing it and Google always has top notch UI. Actually, G+ is having issues because they are ordering comments to sort out the junk and losing chronology because single threads are horrible.
I don't know much about Branch and I haven't seen it used on any major sites. Seems the threaded providers are doing quite well and leading the pack. Nobody complains that Disqus has threads and I see all sorts of ignorant wack jobs successfully using threads in the corners of the Internet.
So yeah, maybe Google and Branch are wrong. Not much of a stretch.
Sorry if t threatens your startup but best to know you're wrong early.
The fact that Threads has a much larger userbase than Mastodon already means that they won't ever really feel threatened by it. The stated reasons why GChat and Facebook Messenger eventually defederated is that it was hard to keep scaling the platform while speaking XMPP, but the unstated reasons were that Messenger and GChat at the time were still very much niche technologies that were jockeying for marketshare in a crowded space.
This time around Threads is already an order-of-magnitude larger than the existing Mastodon Fediverse. Moreover, now Meta has a diverse array of different social products, so there isn't as much pressure on any one product to succeed. If Threads ends up in a dominant position in the threaded-text social network world, that already nets them more users and more opportunities for ad revenue, which they can collect revenue aside their existing properties of Facebook, Instagram, and WhatsApp. On the other hand, interoperating with the Fediverse allows them to be opinionated about what kind of content they allow on their network (e.g. if you're posting from Threads, you can't post sexually explicit content) which can keep them advertiser friendly, while offering a relief valve for the loud minority that will want content disallowed by Meta's content policies. It's a win-win really.
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