Your statement that Seneca committed suicide out of conviction is ambiguous. How would we know if it was Stoicism that compelled him to do so? Nero ordered him to kill himself, so maybe he was afraid of disobeying. There's some evidence in Tacitus's account that Seneca was duplicitous and superficial (see link below).
But that's neither here nor there. I agree that there's mettle in Stoicism, as there is in all Greco-Roman philosophies, compared to the exoteric, more religious alternatives.
Yet for the same reason that we can't say Seneca acted on Stoic principles just because he was a Stoic (because hypocrisy, self-deception, or confusion is quite possible), we should hesitate to say that modern so-called Stoics are purists just because they say so.
I agree, for example, that these Stoic-minded folks may have some admirable beliefs about nature and morality, but that doesn't make them pure Stoics. We're quite eclectic in our beliefs, in this postmodern period. So I'd rather look at the doctrines of Stoicism than at people who call themselves Stoics.
The Stoic's reverence for nature might alleviate the consumer's attachment to material possessions, but remember that Stoicism is ambiguous on precisely that key point. Stoicism is a centrist position between two extremes, as I lay out in the article.
For the ancient Stoics, everything that doesn't corrupt reason and thereby promote vice is morally indifferent. As long as owning material goods isn't illogical (or out of alignment with the natural order), it might be preferred or dispreferred. In a postindustrial society, that's a loophole you could drive a truck through, whereas we might need a sterner warning, given the onslaught of salesmanship in favour of consumer attachments. Buddhism, for example, is more forthright and powerful in that respect.
On the contrary, though, I'd argue that on Stoic grounds, wealth, education, and all other capacities that make us an anomalous species of people are indeed unnatural and therefore vicious. Stoics were thus inconsistent in giving social goods a pass, although the strangeness of our civilizational progress has only perhaps more recently come to a head, in the modern period.
The problem here is that the Stoic imperative that we should live naturally is paradoxical. Animals are natural, but people aren't. Progress for us is a measure of our civilization's anti-naturalness, which is why our progress may be futile and self-destructive.
Also, Stoics held nature to be sacred because they projected intelligent design on it (the Logos). If there were no such natural intelligence and the universe's design were therefore perfectly monstrous, would we still be inclined to submit to natural "regularities"?
In any case, a postindustrial "Stoic" is free to rework the philosophy and to cherry pick the parts he or she likes best.
