It argues the topic pretty well: xz is unsuitable for long-term archival. The arguments are in-depth and well worded. Do you have any argument to the contrary beyond "sour grapes"?
I can understand wanting your project to succeed, it's pretty natural and human, but it's flagrant Antonio had a lot of feels about the uptake of xz compared to lzip, as both are container formats around raw lzma data streams and lzip predates xz by 6 months. His complaint article about xz is literally one of the "Introductory links" of lzip.
Neither is lzip since it doesn't contain error correction codes. You can add those with an additional file (to any archive) e.g. via par2 but then most of the points in the linked rant become irrelevant.
