As much as I like Qubes, wouldn’t this be putting all your eggs in one basket? If an adversary wanted to target you, he’d just have to find his way through Qubes; or suppose the code gets updated with something malicious–you’d be utterly owned in either scenario. Both aren’t trivial to accomplish, but you get my point.
It depends on your perspective. From a pre-Qubes point of view, using just one conventional OS is putting all of your eggs in one basket. Switching to Qubes allows you to set up many different baskets (run many different OSes) and spread your eggs among them. From that perspective, using Qubes is the exact opposite of putting all of your eggs in one basket. It’s a meta-OS.
But you can always go one meta level higher and pose the same objection:
“But you’re using the same meta-OS (Qubes) on all of your machines.” → Diversify meta-OSes
“But you’re using all x86 machines.” → Diversify architectures
“But you’re using computers for everything.” → Diversify into postal mail, telephone calls, radio, morse code, smoke signals, slide rules, abaci, etc.
“But you’re a normal human doing normal human things with other normal humans.” → Diversify into genetic engineering, strong AI, technological singularity, cyborgs, mind uploading, FTL travel, first contact with extraterrestrial sapient lifeforms, etc.
(also, moved these posts into its own discussion as I believe it’s work exploring)
To be fair, it sounds like their current position is a bit more tentative than that:
While we are strongly committed to piloting the use of Qubes OS for SecureDrop, no final decision has been made to move to this new architecture. This decision will require a full audit of this new approach, consideration of alternatives, and extensive validation with SecureDrop’s current user community.
However, I consider this a good challenge for Qubes OS.
Well, that line hasn’t seen changes for 3 years. A lot has changed since: they’ve been through at least two audits and invested thousands of developer hours at this point.
So, yes. While it hasn’t had the final OK. I would say Qubes has been up to the challenge