The limit was a temporary fix.
Shortly before disappearing, Satoshi also repeated over and over that there were more ways that Bitcoin could be successfully DOS attacked than he could count.
The limit (in conjunction with transaction fees) were intended as a DOS attack and spam deterrent. Do you have any evidence that those risks have been mitigated? Do you have any evidence that suggests that 2MB blocks won't be filled to capacity right away? That would leave us where we are today -- with no scaling solutions, wondering how much more un-optimized throughput the network can safely handle.
I don't believe a second, compatible implementation of Bitcoin will ever be a good idea. So much of the design depends on all nodes getting exactly identical results in lockstep that a second implementation would be a menace to the network.
Satoshi's description of how to increase the block size limit was also clearly in the context of a software update. Not an incompatible implementation of bitcoin that essentially attacks the network and intentionally forks from all other client nodes. He even thought compatible alternatives were a bad idea.
One could make the argument that Satoshi thought we could raise the limit as/when needed (as if we needed his authority anyway). In that respect, the question of necessity is subjective and debatable, and it is not immediately clear that an increase to 2MB
now, with no attempts to make throughput more scalable is necessary.
One could not make the argument that Satoshi thought we should increase the block size limit through a contentious hard fork.
All of this is moot. We should be talking in terms of "what is best for bitcoin" -- with respect to users, nodes and miners -- not talking past each other with interpretations of things Satoshi said 5-6 years ago. Not only was Satoshi wrong about some things, but the state of bitcoin has changed a lot. Hell, if we left the codebase as he originally wrote it, those 184 billion bitcoins from the August 2010 value overflow incident would still be with us. Better to work towards bitcoin's principles than aimlessly trying to fit some arbitrary interpretation of Satoshi's words.
As there are already several implementations the menace threat seems overblown. Even if you were to assume that Core was the "one true bitcoin", which version of it is gospel? If miners refuse to upgrade to 0.12 is this an attack? A menace?
It is possible to release an implementation right now with the limit removed. This still isn't an attack. Bitcoin's built in consensus mechanism protects the network.
There is evidence right now that the 1MB limit causes problems. There is only speculation that removing it causes problems.
The reason we can't talk in terms of what is best for bitcoin is because people have different opinions. People prefer speculative drama to mundane truth. The reason we can't work towards Bitcoin's principles is that these are also subject to people's opinion. If you refuse to accept that "What Satoshi said" has any importance all we have is the court of public opinion. In which case your view is as equally valid as mine. How do we resolve that? What are bitcoins principles when it comes to disagreement about what bitcoin is?
With regards to the "appeal to authority" defence. If something is a fact, and somebody happens to state that fact. Any argument that relies on the fact cannot be dismissed by saying "we should not rely on what somebody said". The argument is being made because of the fact, not because of what was said.
The limit was a temporary anti DOS measure, it is now restricting growth of transactions. Those are facts.
IMHO what is best for bitcoin is to allow it to grow unencumbered by artificial limits.