On 2, a few additional quotes from Wikipedia might help (they admittedly don’t directly implicate Guy Rosen, though you’d have to be extremely charitable in assuming he wasn’t party to these decisions):
“ Onavo, which allowed the company to read network traffic on a device prior to its being encrypted, thereby giving the company the ability "to measure detailed in-app activity" and to collect analytics on Snapchat app usage from devices on which Onavo was installed.[12] It did this by creating "fake digital certificates to impersonate trusted Snapchat, YouTube, and Amazon analytics servers to redirect and decrypt secure traffic from those apps for Facebook’s strategic analysis."[13] The program, which was named "Project Ghostbusters" in reference to Snapchat's ghost-shaped logo, was later expanded to include Amazon and YouTube”
“ On January 29, 2019, TechCrunch published a report detailing "Project Atlas"—an internal market research program employed by Facebook since 2016. It invited users between the ages of 13 and 35 to install the Facebook Research app—allegedly a rebranded version of Onavo Protect—on their device, to collect data on their app usage, web browsing history, web search history, location history, personal messages, photos, videos, emails, and Amazon order history. Participants received up to $20 per-month to participate in the program, which was promoted to teenagers via targeted advertising on Instagram and Snapchat. Facebook Research is administered by third-party beta testing services, including Applause and BetaBound, and requires users to install a Facebook root certificate on their phone. On iOS, this is prohibited by Apple's Enterprise Developer License Agreement, as the methods used are intended solely for use by a company's employees (for use cases such as internal software specific to their environment, and internal pre-release versions of apps)”