"Welcome to the galactic federation, humans! All our riches and elite super-science will be yours—immortality, faster than light travel, the tools to build AIs, cures for all your illnesses and a working theory of economics that abolishes poverty and war and provides as much wealth as anybody wants—just so long as you sign this simple easy agreement and consent to make one minor cognitive tweak so that you don't mistakenly destabilize the false vacuum and destroy the universe."
"Um. Wossat, then?"
"We need you to become a group mind. Studies show that in all identified previous cosmoi, individualist tool-using sophonts with access to these technologies harboured splinter groups so deranged that they collapsed the vacuum energy. There are no known exceptions to this rule: apparently telling you collectively not to do something just makes it inevitable. Unless you Borgify first—become a group mind, render your individual mental boundaries permeable to one another, and allow any other human complete access to your thoughts and memories. Group minds generally stick to the terms and conditions voluntarily."
"Uh, let me get back to you on that. What happens if we say 'no'?"
"Then, regrettably, you will discover that you have asked a question to which you really did not want to learn the answer."
Your question: should the human species collectively sign up to (and ruthlessly enforce) the proposed agreement? Discuss the pros and cons.
(Follow-up question: what are the failure modes and unforeseen consequences?)