Teach them tactile signs and go from there.
Watch The Miracle Worker for a notable famous example.
It is a ready-made software that could let them quickly launch a product, and it can deflect the allegations already made of intellectual property theft from Meta hiring former Twitter developers. Of course they could develop their own, but that would take time and added risk.
What benefit would Meta get from federating with the likes of Mastadon? They want profit, and I do not see a way Meta makes money from letting people follow Threads users from Mastodon, KBin, and Lemmy.
Do we even know is Threads will federate at all? I figure meta is using activitypub simply because it’s cheaper and easier than coding their own, not because they intend to federate. Zuck wants private data so he can sell us ads and propaganda. Allowing people to follow from federated servers both denies him user data and the ability to push ads.
As already mentioned, lawsuits are expensive. And if they don’t go your way, they can even get more expensive as you may have to pay the other side’s legal fees.
Also, lawsuits take forever. Even when you go through trial and get a verdict, there is still years worth of appeals coming. Even with a win, you maybe be waiting years.
Settling is far cheaper and sees much faster results, even if you are confident you will win.