Avira,
I generally agree with you.
I don’t , of course , disagree with any of the sources that you have posted.
The concept of being an atheist and outwardly following the Torah, for externalistic reasons such as not wanted to change one’s lifestyle etc is certainly not ok. If a person is a genuine Kofer , unfortunately he must suffer all the consequences in Olam HaEmes that result. I don’t think anyone would say that being “Orthoprax” is ok.
HOWEVER, I have two cautionary qualifiers.
1. It would not be proper to say to someone Jewish who claims to be an athiest , that he should start violating the Torah externally Chas Vishalom, in order to “honestly conform” his actions to his beliefs. Regardless of one’s beliefs, it’s not ok to be Oiver Issurim. His Teshuva will be far easier if he hasn’t abandoned particing Yiddishkeit, as well. So it important that if you are “demolishing orthopraxy” you shouldn’t be misunderstood as saying that people who don’t believe shouldn’t maintain their Yiddishkeit in practice. Doesn’t mean it’s ok, of course.
2. I have met many people who are confused about what they belive , and aren’t sure themselves. Emuna is deeply rotted in the Neshoma. Yiddin who were tremendous Avaryanim RL have suddenly chosen to give ip their lives rather than repudiate their Yiddishkeit.
I’m not sure that some people who think that they are atheists aren’t really lost in the midst of a Nisayon in Emuna. I’ve found, that when engaged in conversation , many will admit to be unsure of what they really feel. What drives the engine of maintaining Yiddishkeit on the outside may often be the Neshoma refusing to lose its grip on what’s most precious to it, althewhile allowing various rationalisations to take place. I would caution against pushing people who say they don’t belive. I’ve heard people say “I don’t know why I still won’t eat Treif/marry a non Jew/ eat on Yom Kippur etc”.
This doesn’t mean it’s ok, it’s not ok to be a Kofer.
But sometimes people need help to realize that they are not as far away as they think. Everyone can do teshuva