It's not necessary to prove that the benefits outweigh the risks. It's trivial to show that in a free country where people are allowed to control their own devices and create and install software of their choosing its trivial for bad guys to communicate in such a fashion as to be 100% immune to any sort of dragnet style surveillance while being equally vulnerable to targeted surveillance whether end to end encryption is banished from mainstream platforms.

There is no benefit to outweigh. For there to be benefits one must convince oneself that we will actively prosecute bad actors via intelligence gathered via holes we will publicly announce we are drilling into previously secure platforms and drug dealers and terrorists will never figure out how to embrace free open source p2p software that doesn't share these disadvantages. There isn't even one smart person among the bad guys or even among the good guys who will create a platform one can connect to with a few clicks amenable to even techno morons. What could possibly go wrong.