I think you paint a much darker picture than the reality is!
From what I’ve read, Nanoleaf plans to stop using Thread, they did not say they stop doing Matter. Nanoleaf has already added more and more WiFi products, I guess they now want to fully commit on WiFi only.
As for Netatmo: They feel the standard is not yet where they want it to be, and that things move to slow. But they also said that they remain in the CSA and will continue to work on Matter, at least according to this article.
In the end, to me this is the usual manager bullshit: Things don’t stick within a couple of months, they get nervous and start blaming whatever they feel is convenient.
Matter is still a very young product, and there are issues everywhere you look. But from a pure engineering perspective, things are progressing nicely: The later iterations do work much better, more and more features in the protocol get polished and the code matures.
Pretty sure initial Zigbee wasn’t all that great. Back than smart home was in it’s infancy and nobody cared. Today, Matter gets just way too much spotlight Rome wasn’t built in a day.
I guess especially these rather succefully established smart home brands with their proprietary protocols feel threatened by Matter. They initially try to adopt it quickly since the market demands it, but they have a hard time to fully commit to it: they’ll always try to sell their own ecosystem as much as possible.
As long as the big ecosystems (Google/Apple/Amazon/Samsung) stick with it, Matter will continue to prosper. There will always be an Eve or some other startup which will make excellent products and focus on the standard.