Another key difference is that #2 violates a bunch of other laws and personal property/privacy boundaries.
The whole point here is that, with a permitted court order and warrant it doesn't break any laws because the law will allow it. That's not a problem. Every day you go into shops which could break "trespass" laws if it were not for the fact that you have permission. Since you do have permission it doesn't. Law enforcement goes
I don't think anyone should be encouraging the use of hacking as a legitimate LEO method to use against our own citizens.
This is an interesting discussion. I don't see hacking as inherently more problematic than, for example, spying on suspects using the many methods that police already do use. However if hacking causes insecurity for other people that's more of a problem.
What I think should be illegal is keeping secret vulnerabilities which might compromise a noticeable proportion of systems in the country (note, I didn't say "large", I would consider 1% of systems "noticable"). The NSA and GCHQ have been doing this when, if they had been publishing vulnerabilities much earlier and more aggressively, it's possible the extra pressure on software companies would have made our systems much safer and more secure. That's a problem.
While I disagree with the use of the 3 party chat solution, and it is a direct violation of necessary privacy and security safeguards, it would function and could be legislated fairly cleanly.
I disagree about the clean legislation. This involves forcing non-technical normal citizens to put themselves at risk by carrying software with them at all times which is designed to work against them. Imagine requiring that all cars had explosives on them so that, in the case they were used for a bank robbery the police could blow them up remotely. That would cause immense problems to make sure that not only could they not be triggered accidentally, that the police couldn't kill random people by mistake, but also that other people couldn't take advantage of the system and the supply of explosives that it provides and use it against the society. Nobody would consider this sane.