I think it won't happen at all, for most of the reasons you gave and more. The feature will never launch. Either because negotiations with various Mastodon instances just falter, or because Meta just loses interest, or both.
Ultimately I think their play here is they want to build their social graph and interaction model around users that are not on their network right now. Every time you boost or share something that came out of Threads, they'll learn something about you -- a non-Meta user -- that they couldn't get just from mining public content. But I think they'll find they're actually not interested much in that data, that its value isn't high enough to justify the hassle.
I just think it's a tempest in a teacup and by the autumn when it's rumoured to be supposedly launching, we'll just stop hearing about it. Or there'll be a trial for a bit and then it'll just get unceremoniously dropped.
Ultimately I think their play here is they want to build their social graph and interaction model around users that are not on their network right now. Every time you boost or share something that came out of Threads, they'll learn something about you -- a non-Meta user -- that they couldn't get just from mining public content. But I think they'll find they're actually not interested much in that data, that its value isn't high enough to justify the hassle.
I just think it's a tempest in a teacup and by the autumn when it's rumoured to be supposedly launching, we'll just stop hearing about it. Or there'll be a trial for a bit and then it'll just get unceremoniously dropped.