What!?!? Yes PRISM is a mass surveillance program. And it's not metadata, it's piping entire content straight from the target to the NSA, in real time. This involves direct filtered data (such as Skype messages/videos) indirectly handed over by participating companies (which is probably all major tech companies in the US at this point), as well as raw upstream (essentially line tapping) data such as provided via STORMBREW. [1]
You're more than 11 years behind the news. Less than a week after Greenwald published his initial ridiculous description of PRISM, it was corrected by the people who actually built the systems at the tech companies. He stupidly thought that the DITU was a machine at the companies that could get any data, when anybody with half a clue could have told him that it's obviously https://en.wikipedia.org/wiki/Data_Intercept_Technology_Unit. The Wikipedia PRISM article's description is very clear and well-cited, and it includes Snowden's slides there to cross reference the description with. https://en.m.wikipedia.org/wiki/PRISM#The_program
The FBI tells the companies to forward the communications of specific targets to the FBI. PRISM is a data integration system that ingests that data from the FBI into NSA systems.
This is overt misinformation. PRISM works directly with the companies (well, "indirectly" to offer plausible deniability). The section you're linking to entirely quotes some random government organization which is obviously an unreliable source on such topics. As is the writing, as opposed to sources, on Wiki.
This [1] is one of the more telling leaks. It's a technical users guide for NSA employees on using realtime Skype surveillance for all modes including video and landline on arbitrary targets. [1] It even includes debugging guides like why an agent might be getting multiple copies of the same message, as happens when somebody being spied on boots up a new device and all of their messages are sent from Microsoft to them (and the NSA) simultaneously, resulting a copy of older messages (from the snooper's perspective).
[1] - https://en.wikipedia.org/wiki/STORMBREW