Most security research does not in fact work this way. Consider, for instance, virtually any memory corruption vulnerability; while it was once straightforward (in the 90s) to work out an exploit "blind", today, researchers virtually always have their targets "up on blocks", connected to specialized debugging tools.
I am a little surprised that we are only now hearing about high-profile researchers getting dinged for actively scanning for actual vulnerabilities in other people's deployed systems. It has pretty much always been unlawful to do that.†
(These are descriptive comments, not normative ones. My take on unauthorized testing of systems in production is complicated, but does not mirror that of the CFAA).
It's for this reason that you should be especially appreciative of firms, like Google and Facebook, that post public bug bounties and research pages --- those firms are essentially granting permission for anonymous researchers to test their systems. They don't have to do that. Without those notices, they have the force of law available to prevent people from conducting those tests.
(Background, for what it's worth: full time vulnerability researcher, started in '94.)
† Caveat: it does depend on the vulnerability you're testing for. There are a number of flaws you could test for that would be very difficult to make a case out of. But testing deployed systems without authorization is always risky.