Good morning 😀
Fragmentation is something intrinsic to free software, I have heard this same argument decades ago talking about GNU/Linux.
My opinion is that fundamentally you are right, but less fragmentation means more centralization (in general terms).
#thenostr is not a software, it is a protocol and each interface implements the NIP's it wants, and that's part of the fun.
I think we have a challenge there, I have also tried to introduce family and friends and they just left in a few weeks.